问题
单项选择题
The officers made it clear that they were letting her go only because that she was old and not because she was above suspicion.
A．for reason
B．due to
C．because of
D．on the grounds
答案
参考答案：D
解析：[分析] 近义词辨析。 because因为(引导原因状语从句)；for reason应为for the reason that；be- cause of和due to后应接名词性短语：on the grounds根据，以……为理由； (如后跟短语，用on the grounds of；如跟从句，用on the grounds that)：因此D为答案。