普拉切克认为情绪的三个维度是（）。

A.愉快-不愉快、紧张-松弛、激动-平静

B.愉快-不愉快、注意-拒绝、激活水平

C.强度、相似性、两极性

D.愉快度、紧张度、确信度

They are talking _______ they were old friends.

A．as if

B．as although

C．even if

D．even though