—What color are they?

—_____. [ ]

A. This is some white

B. They're white

C. They're white sweaters

D. It's white

液态烃管线表面有一层水，是（）造成的。

A、液态烃内的水渗透到管壁

B、管线某处漏

C、空气凝结

D、以上均错误