【题目】Henry made a list of all the possible solutions, ______ helpful in handling the present situation, though.
A.none of which
B.none of them
C.all of which
D.all of them

【答案】B
【解析】考查不定代词。句意：亨利列出了所有可能的解决办法，但并没有一个可以解决当前的问题。none of…全都不……；them指代前句中的solutions。