----does the baby mouse weigh?--About 20grams.A. How muchB. How manyC. HowD. What

问题补充：

----does the baby mouse weigh?

----About 20grams.

A. How much

B. How many

C. How

D. What

答案：

A. How much

(答案→)B. How many

C. How

D. What

解析：疑问词的用法。How much提问不可数名词的数量即后跟不可数名词，还可提问“价格”；how many提问可数名词的数量即后跟可数名词复数；how 意思是“怎样”；what意思是“什么”。根据答句“about 20 grams”意思是大约20克，“grams”是可数名词复数可推断提问多少克，故选B。