高等继续教育 / 大学英语I
正确率：100%
题型描述: 单选题
He studied hard in his youth, _ _ _ _ _ _ _ contributed to his great success in later life.
A. it
B. that
C. what
D. which
He studied hard in his youth, _ _ _ _ _ _ _ contributed to his great success in later life.
A. it
B. that
C. what
D. which
参考答案：