With a lot of problems , the VS troops are having a hard time in Iraq.
A. settled
B. being settled
C. settling
D. to settle
网友回答
A. settled
B. being settled
C. settling
(答案→)D. to settle
解析：考察非谓语动词.句意:由于有好多问题有待解决,联军在伊拉克还会有一段艰难的时刻.不定式做定语表示具体的将要进行的动作,和被修饰词可以是动宾关系,结合语境可知选D.