PT48, S1, Q17 Some classes of animal are so successful

[angela]

17. (E)
Question type: Identify a Flaw
The author assumes that what is true of the whole is true of each individual part. He concludes that if ants as a class exist in every ecosystem, then no individual species of ant could be endangered. Answer choice (E) most clearly captures this flaw.

(A) is out of scope. Whether these two regions are geographically isolated is irrelevant, since they are merely given as two examples of ant habitats (two examples of many).
(B) is out of scope. The comparison of ants to other insects is irrelevant.
(C) is incorrect. The author does not take this for granted.
(D) reverses the flaw, moving from constituents to the whole rather than from the whole to constituents, as the author does in the argument.