题目

如图，A，B两地被池塘隔开，小明通过下列方法测出了A，B间的距离：先在AB外选一点C，然后测出AC，BC的中点M，N，并测量出MN的长为12 m，由此他就知道了A，B间的距离．有关他这次探究活动的描述错误的是( )   A．AB＝24 m          B．MN∥AB   C．△CMN∽△CAB    D．CM∶MA＝1∶2 答案：DTom has to look after ________ because his parents are not at home.A. him B. his C. he D. himself