Over the years I have collected five foreign stamps of them are from the USA.A. hundred

问题补充：

Over the years I have collected five foreign stamps, of them are from the USA.

A. hundred; two hundredsB. hundred; two hundred

C. hundreds of; two hundred D. hundreds; two hundreds

答案：

解析：句意：这几年间我收集了五百张外国邮票，其中二百张是美国的。hundred 百，与数词连用时不用复数，故选B。