People in some countries waste water people in others don’t have enough to drink.A. whileB

问题补充：

People in some countries waste water people in others don’t have enough to drink.

A. while

B. because

C. if

D. so

答案：

(答案→)A. while

B. because

C. if

D. so

解析：考查连词辨析。A当…时；而，可是；B因为；C如果；D于是；句意：一些国家的人浪费水，而其它国家的人没有足够的水喝。根据句意说明上下文之间存在着转折关系。故A正确。