题目

把你的妈妈介绍给同学们，你会说: A . This is my father. B . This is my mother. C . He is my mother. 答案：B如图所示，点A为∠MON的角平分线上一点，过A任作一直线分别与∠MON的两边交于B、C，P为BC的中点，过P作BC的垂线交OA于点D．∠MON=60°，则∠BDC= [     ]A．120°B．130°C．140°D．150°