Which of the following statements has adversative relations

A．My client says he doesn’t know this witness. Further, he denies ever having seen her.

B．He showed no pleasure at hearing the news. Instead, he looked even gloomier.

C．I didn’t know your phone number. Otherwise I should have called you.

D．There are two reasons for my failure. Firstly, I wasn’t well prepared; secondly, my assistant was sick at the time.

从水泥加水开始到水泥浆完全失去可塑性并开始产生强度的时间称为（）。

A.凝结时间

B.初凝时间

C.终凝时间