The books by Mo Yan are so popular that they are in great .
A. quantity
B. progress
C. production
D. demand
网友回答
A. quantity
B. progress
C. production
(答案→)D. demand
解析：A. quantity 数量，B. progress 进步，进展，C. production生产，产量，D. demand要求，需求，句意：莫言的书是这么受欢迎以至于它们需求量很大。In great demand有很大的需求。选D。