The use of "seeming" is incorrect. "Thought" later in the sentence places the sentence in the past tense. "Seemed" is necessary. The use of "was" changes the meaning. The use of ‘in that’ is not as good as the use of "because". "Because" establishes the reason something happened. This is the correct answer.

Note that the original sentence uses "since" and the simple present tense "are" when the present perfect is, in fact, necessary; consider for example, "since 1990 there have been many cases...". Moreover, note that the correct subject of the sentence is "the number of diagnoses," not "the diagnosis of cases". "Quadrupling" would be incorrect. Again the present perfect would have to be used to describe an action that started in the past and has continued up to the present. The correct answer shows this use of the present perfect and uses the appropriate subject: "The number...has quadrupled." This also happens to be the most efficient way of articulating the sentence as no redundancies are present.

The key to this sentence is to recognize the tense and agreement necessary.  This is a hypothetical statement.  Therefore, we need a future tense verb in our sentence.  The sentence is correct as originally stated.  All of the other options change the meaning of the sentence.   

The sentence presents two actions, the passing of the act and the debating of the best way to deal with conflicts. Since the two actions are both completed and since they are presented out of the order in which they actually happened, the past perfect, "had been" is necessary.

Sticking "you" in this sentence is unnecessary with the phrase's imperative mood and the implied subject of "you" in the first part of the sentence, which creates a lack of parallel structure. "You" should be taken out of the underlined portion of the sentence to fix these problems. As only one answer choice makes this change, the correct answer is "and wait for them to be completely finished before returning."

This sentence is a rare use of the subjunctive mood, a verb mood that is used to indicate a hypothetical state or a statement contrary to reality. The subjunctive verb does not use the otherwise more appropriate verb tense "was," as it is indicating a desire of something not real and should use "were." "If I were a betting man" is the only answer choice that uses the correct verb form.

This sentence discusses a condition that is contrary to fact (IF Jerry were in my position, which he is not), and thus uses the subjunctive mood. The subjunctive mood is used to express a wish, suggestion, condition, condition contrary to fact, or command. Because the sentence requires the subjunctive mood, the correct version reads: "Jerry said if he were in my position, he would do the same thing."

When indicating a desire or proclamation, the subjunctive form of a verb—in this case, "be" instead of the usual indicative "is"—should be used.

In the original sentence, the verb "knows" is in the incorrect mood—the indicative. Because of the word "that", we know the sentence contains an order, which means that we must change the verb to the subjunctive mood ("know"). 

The phrase underlined in the sentence uses the modal verb "can," which conditions what might happen in the future. The verb form "clouds" is incorrect as the verb after "can" still needs to feature the singular form necessary with the subject "focus." "Can cloud a leader's judgement" is the best choice among the answer.