-There are many old houses in Beijing, aren't there?

-_______ Only a few remain now.[ ]

A.Yes, they are.

B.No, they aren't.

C.No, there aren't.

D.Yes, there are.

７米水泥电杆在水田，湿地的埋深为（）米。

A.1.3

B.1.4

C.1.5

D.1.2