题目

In most parts of the world, many students help their schools make less pollution. They join environment club. In an environment club, people work together to make our environment clean.Here are some things students often do:No-garbage (无垃圾) lunches. How much do you throw away after lunch? Environment clubs ask students to bring their lunches in bags that can be used again. Every week they will select the class that makes the least garbage and commend (表扬) it to the whole school！No car day. On a no-car day, nobody comes to school in a car, neither the students nor the teachers！Car如图，正方体的棱长为1，线段上有两个动点，且，则下列结论中错误的是（ ）A.B.平面ABCDC.三棱锥的体积为定值D.的面积与的面积相等