There are so many people in the shop. You must _____________ your things. [ ]

A. look at

B. look after

C. put away

D. put on

下列有关水的说法正确的是 [ ]

A、水可以溶解很多物质

B、我国的淡水资源非常丰富

C、用硬水洗衣服效果比用软水好

D、铁丝在氧气中燃烧时，集气瓶底部水的作用是吸收有毒的气体