OG详解-OG4 文法 Q2

Choice D is the best answer. The convention being tested is the use of verbs to express tense. In this choice, the present tense verb “survives” correctly indicates that the wood frog regularly survives subfreezing temperatures by producing large amounts of glucose.
Choice A is incorrect because the past perfect verb “had survived” doesn’t indicate that the wood frog regularly survives subfreezing temperatures by producing large amounts of glucose. Choice B is incorrect because the past tense verb “survived” doesn’t indicate that the wood frog regularly survives subfreezing temperatures by producing large amounts of glucose. Choice C is incorrect because the conditional verb “would survive” doesn’t indicate that the wood frog regularly survives subfreezing temperatures by producing large amounts of glucose.