71. For the sake of the logic and coherence of this paragraph, Sentence 2 should be placed:
Your Answer is
Correct Answer is C
Explanation
Sentence 2 means "Silkworms are portable, therefore, transportation is very cheap." Sentence 1 puts forward two threat factors. Sentence3 emphasizes "but Parmesan thinks that the butterfly checkerspot is a perfect assisted move species", so sentence2 should be placed after sentence3 to express the first reason, and sentence4 puts forward the second reason, that is, "she does not think that the butterfly is not enough to endanger new species. place of residence".