—Excuse me, could you spare me some time?

—Sorry, I ______ a lecture in the hall in a few minutes.

A．have given

B．will have given

C．am giving

D．will be giving

墙面铺装工程中基层表面的（）是保证墙面铺装质量的前提。

A.处理

B.强度

C.稳定性

D.安全性

E.环保性