Giving up my job to go back to full-time education was a big but now I know it was the

问题补充：

Giving up my job to go back to full-time education was a big , but now I know it was the best decision I ever made.

A. project

B. commitment

C. competition

D. ambition

答案：

A. project

(答案→)B. commitment

C. competition

D. ambition

解析：考查名词的辨义。句意为 “当初放弃我的工作重新接受全日制的教育是个了不起的决定，现在我知道那是我作出的最好的决定。” project项目,计划,方案,课题； commitment承诺，许诺，保证； competition比赛，竞争； ambition抱负，雄心，野心。

commitment与后面的decision相呼应，故选B。