Which of the following is NOT a source of adverse effects of inflation on an economy Inflation: （）

A. distorts the information delivered by prices.

B. affects product prices without changing underlying resource prices, such as wages, in the long run.

C. increases the uncertainty accompanying investment and other activities involving future payments.

下列关于水的说法正确的是

A．我们平时应多饮用很纯净的水，防止有毒物质进入体内

B．所有的天然水都不能饮用

C．人体内含有约2/3体重的水，故人每天不用喝水也可以

D．人类可利用的水只占自然界水的极少量，我们应节约用水