The end of this sentence needs to logically convey whether computer technology can power economic growth in the same way that the steam engine and the printing press used to power economic growth when they were important. "whether computer technology can power economic growth like the steam engine and the printing press", "whether technology can power economic growth as the steam engine and the printing press do", and "if computer technology can power economic growth as the steam engine and the internal combustion engine of the past do" all compare computer technology to the PRESENT impact of the steam engine and the printing press on economic growth – clearly illogical as those have no impact today on economic growth today. "whether computer technology can power economic growth the way the steam engine and the printing press did" and "if computer technology can power economic growth like the way the steam engine and the printing press did" make the proper comparison between computer technology today and the steam engine and printing press in the past. "if computer technology can power economic growth like the way the steam engine and the printing press did" is wrong, however, because of the redundant and incorrect structure “like the way” and the incorrect conditional “if” that starts the clause. "whether computer technology can power economic growth the way the steam engine and the printing press did" uses the correct “whether” and makes a logical and proper comparison.

This problem features several subtle meaning-related errors, errors that are much easier to spot and understand if you use good Decision Points strategy to identify the major differences between answer choices.

Note first that choices "the approval ratings among his constituents and the stock market dropping rapidly, the president announced a series of spending initiatives to try stimulating"/"the approval ratings among his constituents and the stock market dropping rapidly, the president announced a series of spending initiatives trying to stimulate" and "the stock market and the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives to try and stimulate"/"the stock market and with the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives that will try to stimulate"/"the stock market and the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives to try to stimulate" flip the order of "the approval ratings" and "the stock market." Is that important? In "the approval ratings among his constituents and the stock market dropping rapidly, the president announced a series of spending initiatives to try stimulating" and "the approval ratings among his constituents and the stock market dropping rapidly, the president announced a series of spending initiatives trying to stimulate", "the approval ratings among" applies to both nouns that follow it ("his constituents and the stock market"), creating an illogical meaning: the stock market doesn't give approval ratings! By changing that order and putting the stock market first, "the stock market and the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives to try and stimulate", "the stock market and with the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives that will try to stimulate", and "the stock market and the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives to try to stimulate" fix that error, keeping "the approval ratings among" separate and applicable only to "his constituents."

In choice "the approval ratings among his constituents and the stock market dropping rapidly, the president announced a series of spending initiatives trying to stimulate", the phrase " the president announced a series of spending initiatives trying to stimulate" assigns the verb "trying" to the spending initiatives. But that's not logical either - initiatives are inanimate and can't "try" to do anything; it's the president trying to stimulate the economy, not the initiatives. So "the approval ratings among his constituents and the stock market dropping rapidly, the president announced a series of spending initiatives trying to stimulate" is also incorrect for a meaning reason.

"the stock market and with the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives that will try to stimulate" makes a very similar meaning error: by saying "spending initiatives that will try to stimulate" this choice makes it seem again like the initiatives will try, and that just cannot be true.

Between "the stock market and the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives to try and stimulate" and "the stock market and the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives to try to stimulate", there is a one-word difference: "the stock market and the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives to try and stimulate" has "try and stimulate" while "the stock market and the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives to try to stimulate" has "try to stimulate." While in common speech you may be accustomed to hearing the two used interchangeably, the "and" creates a totally different meaning - by linking two parallel verbs ("try" and "stimulate"), "and" creates the meaning that those two actions are independent. That's an incorrect meaning: "stimulate" is exactly what the president is trying to do. "Try to stimulate" conveys that meaning properly, making answer choice "the stock market and the approval ratings among his constituents dropping rapidly, the president announced a series of spending initiatives to try to stimulate" correct.

In analyzing the decision points between the five answer choices, you should first notice the difference between “in ascribing” in "in ascribing these ailments to a psychological disorder", "in ascribing a psychological disorder as the cause for these ailments", and "in ascribing a psychological disorder to these ailments" and "if these ailments are ascribed" in "if these ailments are ascribed as the cause for a psychological disorder" and "if these ailments are ascribed to a psychological disorder". Additionally, you should see that "if these ailments are ascribed as the cause for a psychological disorder" and "in ascribing a psychological disorder as the cause for these ailments" contain the words “as a cause” while the other choices do not. Probably the easiest of those decision points to assess is the addition of “as a cause”. The word "ascribe" already means "to credit or assign, as to a cause or source" so "if these ailments are ascribed as the cause for a psychological disorder" and "in ascribing a psychological disorder as the cause for these ailments" are redundant. For "in ascribing these ailments to a psychological disorder" and "in ascribing a psychological disorder to these ailments" the use of the modifying phrase “in ascribing” illogically modifies the patients, suggesting that the patients are the ones doing the ascribing. Clearly, it is the doctor who is doing the ascribing and the “if” clause, which does not then modify the patients, makes the meaning logical. Correct answer is "if these ailments are ascribed to a psychological disorder".

This problem (like many others) tests logical meaning. Note the use of the word "other" in choices "As some of the busiest airports and ports in Europe, the United Kingdom has far more invasive species of certain types than does any other European country." and "With some of the busiest airports and ports in Europe, the United Kingdom has far more invasive species of certain types than does any other European country.", and compare that to the usage in "With some of the busiest airports and ports in Europe, the United Kingdom has far more invasive species of certain types than does any European country."/"Because of some of the busiest airports and ports in Europe, the United Kingdom has far more invasive species of certain types than does any European country."/"Because it has some of the busiest airports and ports in Europe, the United Kingdom has far more invasive species of certain types than any European country does.". Can the UK have more invasive species than any European country, when it is a European country itself? Logically, no - it can have the most of any country in Europe, but not more than any country. The best it can do is "tie" itself. So this sentence requires the use of "other" to be logically correct.

Then notice the major difference between "As some of the busiest airports and ports in Europe, the United Kingdom has far more invasive species of certain types than does any other European country." and "With some of the busiest airports and ports in Europe, the United Kingdom has far more invasive species of certain types than does any other European country.". The UK has some of the busiest (air)ports, but it is not itself the busiest airports and ports. So "As some of the busiest airports and ports in Europe, the United Kingdom has far more invasive species of certain types than does any other European country." is illogical, meaning that "With some of the busiest airports and ports in Europe, the United Kingdom has far more invasive species of certain types than does any other European country." must be the correct answer.

This problem provides two very clear decision points for you to get started:

1) "they" vs. "it" as the first word of the sentence

2) "that of" vs. "those of" vs. (no possessive) in relation to "the Medieval period"

The key to both of these is recognizing the subject of the sentence which is "global temperatures." Since temperatures is plural, the pronoun that corresponds to them must be "they" and you can eliminate choices "it has only recently eclipsed the Medieval period, during which, scientists theorize, a" and "it has only recently eclipsed that of the Medieval period, during which scientists theorize a".

Then notice that the comparison is between current global temperatures and the temperatures during the Medieval period; you cannot logically compare "temperatures" with the timeframe, so you need to have "those of" (which "they have only recently eclipsed those of the Medieval period, during which scientists theorize that a" and "it has only recently eclipsed that of the Medieval period, during which scientists theorize a" have but "they have only recently eclipsed the Medieval period, during which scientists theorize that a" does not) to properly draw the comparison.

Between "they have only recently eclipsed those of the Medieval period, during which scientists theorize that a" and "they have only recently eclipsed those of the Medieval period, during which, scientists theorize, a", notice that the only difference is commas around "during which." Why is that important? Here you're dealing with a tense/timeline decision. Since "theorize" is present-tense but the Medieval period is clearly in the past (even if you're not a historian, the fixed past tense "sent" outside the underline tells you that those volcanoes were in the past), you cannot have "scientists theorize" as part of the phrase "during which." The scientists currently theorize that volcanoes caused the global warming, so you need to separate that subject-verb from the modifier "during (the Medieval period)." This means that answer choice "they have only recently eclipsed those of the Medieval period, during which, scientists theorize, a" is correct.

In this sentence correction problem, it is very easy to access the decision points because there is only one word underlined! So the difference between those five choices to start the sentence obviously matters and you need to figure out why.

To do this you must look at the entire sentence - a classic example of the “Whole Sentence Matters” device used by testmakers. The primary issue is which of these modifiers creates logical meaning with the rest of the sentence. Clearly, the phrase must modify “rainforests”- and do rainforests “have” or “possess” a portion of the earth’s surface? Or do they just represent it? They simply are that portion of the earth’s surface, so only “as” "being" and “although accounting for” could be correct choices. Answer choices "With" and "Despite having" illogically suggest that rainforests have or are with 7% of the world's surface areas.

For the choice between "As", "Being" and "Although accounting for", the decision comes down to the meaning of the sentence. The rest of the sentence goes on to talk about what a large impact the rainforest have on the planet, but the introductory phrase talks about how rainforests are (only) 7% of the earth’s surface. Answer choices "As" and "Being" illogically suggest that the reason they have such a large impact is because they are such a small percentage of the earth's surface area! With that in mind, you see that the sentence requires a transition to set up a logical meaning – although rainforests represent a small area, they have a huge impact. Therefore, the phrase “although accounting for” is necessary, and the correct answer is "Although accounting for".

The only decision points in this problem are the choice between "and" and "or" at the end of the series and the choice in how the series are constructed. Each one of these separate things - genetic engineering, ionizing radiation, and sewage sludge - is something that if true would prevent anything from being labeled organic. You do not need all three to be disqualified from being labeled organic so the word "and" is incorrect - it must be "or". Similarly the words "as well as" in "genetic engineering or ionizing radiation, as well as the use of sewage sludge," create the same problem so you can eliminate "genetic engineering or ionizing radiation, and with sewage sludge,", "genetic engineering or ionizing radiation, as well as the use of sewage sludge,", and "genetic engineering, ionizing radiation, and sewage sludge" for this reason. "genetic engineering or ionizing radiation, or the use of sewage sludge," is a fairly easy-to-recognize error of parallelism in the series so correct answer is "genetic engineering, ionizing radiation, or sewage sludge".

"supermoon, which is the full or new moon that occurs when the moon is at or near its closest approach to the Earth, and which can make the moon appear" contains a sentence construction error: the subject "supermoon" never gets a verb, so we are left with a fragment. "supermoon is the full or new moon that occurs when the moon is at or near its closest approach to the Earth and can make the moon appear" suggests either that "a supermoon" can make the moon appear larger or that "the moon" can make the moon appear larger, but neither of these construals is acceptable, since a supermoon is the moon and one would never say that "the moon makes the moon appear larger." "supermoon is the full or new moon that occurs when the moon is at or near its closest approach to the Earth and appears" correctly suggests either that "a supermoon" appears much larger than the moon typically does or that "the moon" appears much larger than the moon typically does. In "supermoon is the full or new moon that occurs when the moon is at or near its closest approach to the Earth, a position which causes itself to appear", the phrase "causes itself" does not work logically, since the position does not make itself appear larger. "supermoon, which is the full or new moon that occurs when the moon is at or near its closest approach to the Earth, causes the moon to appear" suggests that the "supermoon" causes the moon to appear larger, but that claim is illogical, since the "supermoon" is the moon. Note: "supermoon is the full or new moon that occurs when the moon is at or near its closest approach to the Earth and can make the moon appear" and "supermoon is the full or new moon that occurs when the moon is at or near its closest approach to the Earth and appears are both characterized by the same flexible/fuzzy subject-verb relationships. In "supermoon is the full or new moon that occurs when the moon is at or near its closest approach to the Earth and can make the moon appear", either "a supermoon" or "the moon" (first instance) could be legitimately posited as the subject of "can make"; in "supermoon is the full or new moon that occurs when the moon is at or near its closest approach to the Earth and appears", either "a supermoon" or "the moon" (first instance) could be legitimately posited as the subject of "appears." What's important is that whichever construct one favors, the reasoning above holds: "supermoon is the full or new moon that occurs when the moon is at or near its closest approach to the Earth and can make the moon appear" doesn't work and "supermoon is the full or new moon that occurs when the moon is at or near its closest approach to the Earth and appears" does.