单选题 Office branches are located______ the metropolitan area.

A、 (A) on
B、 (B) at
C、 (C) about
D、 (D) throughout

【正确答案】 D

【答案解析】Throughout is used to mean many different locations within a city or another area. Choices (A) and(B) may be used with street locations but not with cities. Choice (C) means concerning.