Choice (E) is correct. To find the answer to Analogy questions, use the Kaplan Method for Analogies. Create a bridge linking the words in the stem pair. In this case, to
hem a
skirt to make it shorter. Then look for choices that use the same bridge. Choice (E), to
trim hair is to make it shorter, is the only one that works.
Choice (A) is wrong, because to
erase a
mark is not to make it shorter, but to make it disappear altogether.
Peeling a
banana does not have a shortening effect either, so Choice (B) is out.
Embroidering a
sweater (Choice C) is a same subject trap, for those who still had clothes on their minds. The GRE loves to provide this trap, hoping that test-takers become more concerned with the subject then with the relationship. Beware of such choices. Finally, in Choice (D),
boiling water will not make it any shorter.