We tried to settle the problem with them as soon as possible but they seemed to ( ) sincerity.
A、
be lacking in
B、
lack of
C、
be lack for
D、
lack in
【正确答案】：A
【题目解析】：
本题考查常见动词的固定词组搭配。
be lacking in缺乏…，固定搭配。其他动词表达有lack for...意为“缺乏...”。
句意：我们试图尽快和他们解决问题，但他们似乎缺乏诚意。