The correct response is (C). The sentence is stating that, as the cost of utilities skyrocket,
people will need homes that are smaller and more energy-efficient.
Response (A) is incorrect because “will explode” is in the future perfect tense and “precipitates”
is a plural verb in the present tense.
Response (B) is incorrect because “will explode” is in the future perfect tense and “precipitate” is
a singular verb in the present tense.
Response (D) is incorrect because the verb “precipitates” is in the present tense and because
the first clause of the sentence makes sense by itself. Therefore, the word “which” is needed
rather than “that.”
Response (E) is incorrect because, although “will precipitate” is the correct tense, the second
clause should begin with “which” rather than “that” because the first clause expresses a
complete idea.