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52. The struggle against sand storm will not end _____ victory unless we pay much attention to the balance of nature.

52. The struggle against sand storm will not end _____ victory unless we pay much attention to the balance of nature.

A. at                                   B. in                                   C. for                           D. With

52. The struggle against sand storm will not end _____ victory unless we pay much attention to the balance of nature.