Question

Over the past decades, sea ice _______ in the Arctic as a result of global warming.

A. had decreased     B. decreased    C. has been decreasing     D. is decreasing

Answer 1

C

解析:

考查時態(tài)。句中有Over the past decades謂語動詞用現(xiàn)在完成時或現(xiàn)在完成進(jìn)行時。