The information in the table shows that while many people apply for archaeology jobs at museums and universities, the actual number of jobs is much smaller, so only 8% and 13% of applicants will find those jobs.  This supports the claim that “the demand for these jobs outstrips the number of positions available, making these jobs difficult to get.” This makes " Yes, because the information in the table validates the claim made in the last sentence of the paragraph."  

Among the other answer choices:  "Yes, because the information in the table proves that archaeology professors spend most of their time on teaching and writing" is incorrect as the table shows what types of jobs are available but does not talk about the activities that take place within the “University” jobs column.  "No, because the information in the table shows that most archaeologists apply for jobs at universities" is incorrect because while the table does show that more people apply to universities than any of the other four categories, that doesn’t mean that “most” (more than ½) do.  Also it is perfectly consistent with the author’s point that many people apply to university jobs (that’s “demand”); the author just adds that not many of those jobs exist, and the table also supports that.  And "No, because the information in the table does not specify whether the jobs at museums are curator jobs" is incorrect because, again, the “because” reason here is consistent with the author’s point that there aren’t many jobs as university professors and museum curators. If the very small number of museum jobs were to even include museum jobs that aren’t for curators, that reinforces the point that the jobs people tend to visualize as archaeology jobs aren’t, in fact, what most archaeologists do.

While this table is somewhat related to the topic of earthworms’ impact on soil fertility, note that the passage doesn’t directly link the metrics in the table (corn height, in particular) to soil fertility itself.  Without that direct connection, the table is out of scope of the passage’s subject matter - it’s somewhat related but doesn’t quite fit. That makes choice "No, because the information displayed in the table is not directly referenced by or connected to the passage. 'a good option.

But as in most SAT questions that provide you with Yes/No answer choices that include reasons, this problem is best attacked with process-of-elimination.  With choice "Yes, because it proves that corn can only grow when there are more than 62 worms per square meter.", recognize the extremely strong language in “prove” and “only” - the table does show that for these 7 locations in Manitoba, corn grows and the worm count is above 62 worms per square meter.  But these seven locations don’t prove that that is the only case; there could very well be other corn-growing locations with lower worm counts that just weren’t part of this study. So "Yes, because it proves that corn can only grow when there are more than 62 worms per square meter." has logical problems, and like "No, because the information displayed in the table is not directly referenced by or connected to the passage." alerts you to the topic doesn’t directly connect to the passage, which doesn’t call for proof of worm density in soil.

With "Yes, because it demonstrates that corn grows higher when there are more earthworms in the soil."  the logic of the “because” portion is sound (the table does show that corn grows higher when worm concentration is higher) but the passage doesn’t include language to connect corn height to soil fertility, so this lesson doesn’t directly connect to a main point of the paragraph.

And with "No, because corn is not the only type of plant that should be able to grow in soil fertilized by earthworms.", note that if the table were connected to the passage in language it could very well be helpful - showing that earthworm concentration is the best predictor of corn height could very well make the case that earthworms are extremely influential with regard to soil fertility. The table doesn’t have to prove that this is true for all plants in order for this finding from one type of plant to help demonstrate the case that worms are good for the soil. So "No, because corn is not the only type of plant that should be able to grow in soil fertilized by earthworms." is wrong in that the issue with the table isn’t that it only includes corn, but that the passage doesn’t directly connect the idea of corn height to soil fertility.