题目

构件1和构件2形成如图a所示的榫卯结构，构件1的结构如b所示。下列构件2的设计方案中正确的是（ ） A . B . C . D . 答案：D A lot of food __around the world every year. We must do something for it.A. was wasted B. is wastedC. wasted D. will be wasted