Andy was crying in his room just now，but he wouldn’t tell me_______ made him so sad.

A．why it was that

B．why was it that

C．what it was that

D．what was it that

以下选项中，不属于工作评价必须遵循的原则是（）

A.系统性原则

B.实用性原则

C.标准化原则

D.满意性原则