They are ______ parents and let their children make their own decisions on different things.
 
【正确答案】 B
【答案解析】 句意:他们是开明的父母,让他们的孩子在不同事情上自己做决定。liberal开明的,宽容的。liberate解放,释放。liberty自由,许可。liable有责任的,有义务的。