This is the plane he went to Shanghai business.A. where for aB. by which on theC. in

问题补充：

This is the plane he went to Shanghai business.

A. where, for a

B. by which, on the

C. in which, on

D. where, on

答案：

A. where, for a

B. by which, on the

(答案→)C. in which, on

D. where, on

解析：定语从句，by plane = in/ on the plane ；出差on business。