题目

 I arrived at my mother’s home for our Monday family dinner. The smells of food flew over from the kitchen. Mother was pulling out quilt(被子)after quilt from the boxes, proudly showing me their beauties. She was preparing for a quilt show at the Elmhurst Church. When we began to fold and put them back into the boxes, I noticed something at the bottom of one box. I pulled it out. “What is this?” I asked.     “Oh?” Mom said, “That’s Mama’s quilt.”       I spread the quilt. It looked at if a group of school children had pieced it together; irregular designs, c读下图完成问题。 图中所示的人工建筑工程，主要是用来                                                                   （    ）        A．实施小流域开发                                 B．蓄水—灌溉—防洪等        C．拦沙—泄水—防治泥石流                   D．固坡—护山—防治山体滑坡