—All the volunteers were very tired but of them took a rest.—They were busy looking for t

问题补充：

—All the volunteers were very tired, but of them took a rest.

—They were busy looking for the missing people.

A. neither

B. all

C. both

D. none

答案：

A. neither

B. all

C. both

(答案→)D. none

解析：Both两者都； Neither表示两者都不；all所有都；none一个也没有。句意：所有的志愿者都很累了，但是他们中没有一个人休息一下。——他们正在忙着寻找失踪的人们。结合语境可知选D。