The members in the testing team were quite （）and could schedule

The members in the testing team were quite （）and could schedule upon request.
A、sophisticated
B、gentle
C、substantial
D、flexible
【正确答案】：D
【题目解析】：sophisticated复杂的；gentle温和的；substantial大量的，实质的；flexible灵活的，柔韧的。根据句意：测试小组成员(时间)非常灵活,可以根据自己要求改变时间表，应选D。