An on the back (),there is a map.A bookcase B floor C wall D classroom

问题描述:

An on the back (),there is a map.A bookcase B floor C wall D classroom
And on the back (),there is a map.A bookcase B floor C wall D classroom

C wall 在后面的墙上挂着一张地图,根据back把AB排除,再根据on介词,排除D.因为D应该和in搭配.谢谢!