Which choice completes the text so that it conforms to the conventions of Standard English?
A
are affecting
B
will have affected
C
will affect
D
affected
Explanation
Correct answer: D.
Choice D is the best answer. The convention being tested is the use of verbs to express tense in a sentence. In this choice, the past tense verb "affected," used in conjunction with the phrase "during this time," correctly indicates that the dust storms occurred in the 1930s.
Why the other choices are wrong
Choice A
Choice A is incorrect because the present progressive tense verb "are affecting" doesn’t indicate that the dust storms occurred in the 1930s.
Choice B
Choice B is incorrect because the future perfect tense verb "will have affected" doesn’t indicate that the dust storms occurred in the 1930s.
Choice C
Choice C is incorrect because the future tense verb "will affect" doesn’t indicate that the dust storms occurred in the 1930s.