Please tell me how global warming . I am still in the dark.A. came byB. came outC. came to

问题补充：

Please tell me how global warming . I am still in the dark.

A. came by

B. came out

C. came to

D. came about

答案：

A. came by

B. came out

C. came to

(答案→)D. came about

解析：动词短语辨析。A经过；B出版，发行；C涉及到，谈及；D产生，发生；句意：请告诉我全球变暖是如何产生的，我仍然不清楚。根据句意说明D正确。