問題詳情
40. Scientists say feral pigeons are a valuable way of probing contaminants in environment, ___ theyare exposed to the same air, water, food and other factors as humans, and don’t venture far fromhome.
(A) although
(B) hence
(C) because of
(D) since
參考答案
答案：[無官方正解]
難度：計算中-1
書單：沒有書單，新增