Some people in the group complained that their tour（ ）better organized.
A、
could be
B、
may have been
C、
might be
D、
could have been
【正确答案】：D
【题目解析】：
情态动词，情态动词+have done， 本可以怎样，但实际上并没有怎样。表示抱怨，不满。“组内的一些人抱怨道他们的行程本可以安排的更好”。
Some people in the group complained that their tour（ ）better organized.
Some people in the group complained that their tour（ ）better organized.
could be
may have been
might be
could have been
情态动词，情态动词+have done， 本可以怎样，但实际上并没有怎样。表示抱怨，不满。“组内的一些人抱怨道他们的行程本可以安排的更好”。