The new buyer identified a dozen new sources for the material, proved to be reliableA. m

The new buyer identified a dozen new sources for the material, proved to be reliable．
A. most of them
B. most of which
C. most of whom
D. most of those

A. most of them(答案→)B. most of whichC. most of whomD. most of those解析：句意：新的买方确定了十几个新的来源为材料，大部分被证明是可靠。先行词是物the material，应该用which做介词宾语，引导非限制性定语从句，whom代人，其他表示定语从句的关系词，故选B。考点: 考查定语从句的用法。

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