题目

阅读下面材料，从每题所给的A、B、C、D四个选项中，选出符合材料意思的最佳选项。 Do you know Buy Nothing Day? Before Christmas we can see advertisements (广告) on TVs, they ask people to Buy, buy, buy!. People buy many things. But▲ . So they start (开始) an interesting day — Buy Nothing Day. They don't want people to go shopping on that day. Buy Nothing Day is on November 29. It is after Thanksgiving Day and often the first day of Christmas shopping. The idea for Buy Nothing Day starts in Canada first. Now people all over the world(全世界) have Buy 如图，四边形ABCD，∠A＝∠C，AD∥BC．请问四边形ABCD是否是平行四边形？为什么？