— There used to be a lot of fish in the lake many years ago.— Yes but there are very now

问题补充：

— There used to be a lot of fish in the lake many years ago.

— Yes, but there are very now because of the pollution.

A. few

B. fewer

C. little

D. less

答案：

(答案→)A. few

B. fewer

C. little

D. less

解析：根据句意，鱼类由于污染而变少了，又因fish此处是可数名词，故选A。