The north Bering Sea one of the world’s richest feeding grounds for whales, walruses and sea birds, is warning to the point ________ animals are being forced to adapt or suffer the consequences．

1. A.
   when
2. B.
   which
3. C.
   where
4. D.
   there

The north Bering Sea one of the world’s richest feeding grounds for whales, walruses and sea birds, is warning to the point       animals are being forced to adapt or suffer the consequences.

A．when        B．which       C．where       D．there