THE CORRECT ANSWER IS (A). THE SUBJUNCTIVE MOOD IS APPROPRIATE FOR...

34. The correct answer is (A). The subjunctive mood is appropriate for this sentence

since it ostensibly involves a contrary-to-fact situation. Either of two phrases—If empty

space were or Were empty space—would be perfectly acceptable here. Choice (A) employs

the latter phrase. Choices (B) and (C) incorrectly use the present tense is, which is

inappropriate for expressing the subjunctive mood. Choice (B) is also wordy. Choice (D)

is not idiomatic. (That should be replaced with If.) Choice (E) incorrectly uses the past

tense was.