选择题

________ is the only president ever to resign in the history of the United States of America.

A、 John K. Kennedy
B、 Richard Nixon
C、 Dwight D. Eisenhower
D、 Bill Clinton

【正确答案】 B

【答案解析】

Richard Nixon is the only president ever to resign in the history of the United States of America because of the involvement of members of his administration in the Watergate scandal.