30. Kate _____ by the teacher for she had made an excellent contribution to group discussion.
A
praised
B
was praised
C
has praised
D
has been praised
关键词是had made， 可知表扬praise 应该发生在做贡献之后，因此用一般过去时，故选B.
本题是语法知识题。本句意思是：凯特别老师表扬因为她在团队讨论中做出了杰出的贡献。此处故选B.
把握不准时态。