Answer:
I believe the answer is,
"It foreshadows the Charlie will only become a little bit more intelligent, and he will not understand why."
Also, that story is bloody amazing.
Object of a preposition is a word which follows a preposition. Since there are only two prepositions in this sentence, <em>during </em>and <em>despite, </em>the objects of those prepositions are experiment and risks. The correct answer is D.
Cisneros plays around with connotation and denotation with the word only by using the word in different ways. As in this example sentence, it says they are the only daughter, inferring that there is one female child, but they say they are only a daughter, inferring that they feel they can be nothing more than a daughter.