A. The average age of applicants to United States literature Ph.D. programs has changed markedly over the past four years.
Correct because this choice doesn’t explain why decrease in the number of applications are occurring. The reverse may very well be true.
Average age may change in any direction but the number of application may rise or fall unrelated of this age.
Therefore this choice is correct.
B. The number of international students applying to literature Ph.D. programs in the United States has declined by nearly half in the past four years.
Incorrect because this choice weakens the conclusion by showing that the decrease actually occurred because of international students, not US students as the stem says.
C. The cost of attending a literature Ph.D. program in the United States has more than doubled in the past four years.
Incorrect because this choice weakens the conclusion by showing that there is another factor that decreased the number f applications other than the decreasing interest of US students. High cost may be deterring who are actually interested in studying literature.
D. The average number of Ph.D. programs that the average Ph.D. applicant applies to has dropped from seven to four over the past four years.
This choice also weakens by showing that the overall number of applications decreased but the number of interested students is still the same.
E. The number of Ph.D. programs reporting data to American College Daily has declined precipitously since the publication stopped compensating for such submissions three years ago.
If universities stopped reporting to the organization whose report we are talking, then this organization may simply don’t know how many applications are being received.
So A
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