A、  B、  C、  C所给出的问题是一个询问原因(why)的问句。选项(A)是回答有关when的提问，所以被排除。另外还要注意问题中的call(打电话)与选项(B)中的call(将……称为，叫做)的含义是不一样的，不要混淆

Who’s going to show the new employees around?
(A) The show is on Monday.
(B) I think Ms. Stetson will.
(C) Actually, we need something more square.

Why did Jeffery call earlier?
(A) After 9 o’clock.
(B) You can call him Jeff.
(C) He called to invite us to dinner.