Which of the following sentences is INCORRECT？A．I bought the book for which you asked.B．Wh

Which of the following sentences is INCORRECT？

A．I bought the book for which you asked.

B．Who that you had ever seen is stronger than him？

C．The man and the horse which fell into the river were drowned.

D．This is the place which we visited last year.

请帮忙给出正确答案和分析，谢谢！