Harry Potter is so interesting a book that lots of teenagers like to read _A. it B. thisC.

问题补充：

Harry Potter is so interesting a book that lots of teenagers like to read _

A. it

B. this

C. that

D. one

答案：

(答案→)A. it

B. this

C. that

D. one

解析：考查代词的用法。由句意可知Harry Potter这本书很有趣，以至于很多年轻人都喜欢读“它”。空缺处是再次提及这本书，故答案选A。it=the+名词单数，特指。