Question

The children, _____ had played the whole day long, were worn out.

A．all of what	B．all of them
C．all of whom	D．all of which

Answer 1

B

解析试题分析：句意为：那些孩子玩了一整天了，他们筋皮力尽了。从非限制性定语从句的角度理解，what /them不属于定从中的关系词；应排除AB，而先行词为the children 故为C。
考点:定语从句的考查。