—I wonder why Mr. Green looks quiet in class.
—I'm not sure, but he（）a small accident driving here.

A. could have

B. might have

C. might have had

D. must have had

人的性格是个性心理即非智力因素的核心部分，其特征结构包括（）四类

A、态度、意志、情感、理智

B.态度、热情、意志、认知

C.认知、意志、情感、理智

D.态度、意志、情绪、认知