The book, are true stories about great scientists of the 20th century, is well worth reading.
A. which
B. what
C. in which
D. of which
网友回答
A. which
B. what
(答案→)C. in which
D. of which
解析：考查定语从句。这个定语从句是一个倒装句，陈述语序true stories about great scientists of the 20th century are in which.which指代先行词the book做介词in的宾语。