题干
Mr. Wang teaches English in this school.
A：them
B：their
C：they
D：themselves
答案(点此获取答案解析）
A
Mr. Wang teaches English in this school.
A：them
B：their
C：they
D：themselves
，其苯环上的二溴代物有9种同分异构体，由此推断A苯环上的四溴代物的同分异构体的数目有（ ）