This is not an economical way to get more water; ,it is very expensive.A. on the contraryB

This is not an economical way to get more water; ,it is very expensive.
A. on the contrary
B. on the other hand
C. in a word
D. rather than

(答案→)A. on the contraryB. on the other handC. in a wordD. rather than解析：本题的含义是这不是得到更多水的经济方式，相反，它的价格非常昂贵，on the contrary表示相反的意思，与题意较符合，故本题选A。

这个问题的回答的对