.exercise early in the morning has become part of his retired life .A. Take .B. TakesC. Ta

问题补充：

.exercise early in the morning has become part of his retired life .

A. Take .

B. Takes

C. Taking

D. Taken

答案：

A. Take .

B. Takes

(答案→)C. Taking

D. Taken

解析：本题的含义是早起锻炼成为他退休生活的一部分，主语不能为动词原形，可用动名词taking，故本题选C。