He looked rather untidy as there were two buttons from his coat.A. loosingB. losingC. off

问题补充：

He looked rather untidy as there were two buttons from his coat.

A. loosing

B. losing

C. off

D. missing

答案：

A. loosing

B. losing

C. off

(答案→)D. missing

解析：missing 缺少的; a book with some missing pages. （缺页书）