问题补充：
My most famous schoolmate of all，who really left his mark on America，was Tom，my contemporary when I was at a primary school.
A. one
B. the one
C. he
D. someone
答案：
A. one
(答案→)B. the one
C. he
D. someone
解析：解析:the one作同位语，指代上文中的my most famous schoolmate of all。one作代词表示泛指，泛指某人或某物；he作主语，不作同位语；someone意为“某人”，泛指某人。故答案为B.
