He wrote a lot of novels regarded as masterpieces.A. dozens of themB. dozens of whichC.

问题补充：

He wrote a lot of novels, regarded as masterpieces.

A. dozens of them

B. dozens of which

C. a dozen of which

D. dozen of that

答案：

A. dozens of them

(答案→)B. dozens of which

C. a dozen of which

D. dozen of that

解析：dozen“十二”，hundred，thousand等前用数字修饰时不用复数，且不与of连用，排除C、D；泛指“几十”，“几百”等时可以与of连用，例：dozens of...“几十个......”。句中有逗号，是非限制性定语从句，故选B。选A的话，应该在A前面加and。故选B。