题目

阅读理解。阅读下面短文，根据短文内容，从所给的A、B、C、D四个选项中，选择最佳选项。    Mother’s Day is an important day. It’s a day children can show their mothers how much they love them. On Mother’s Day, many children give flowers to their mothers. This makes them very happy.     Mrs. Green lived in a small street. She had a flower shop. People who lived near her store were poor. The children didn’t have money to buy flowers. Mrs. Green helped them. The children worked one hour for Mrs. Green. They cleaned the windows in the store. Then Mrs在盛有稀H2SO4的烧杯中放入用导线连接锌片和铜片，下列叙述正确的是（ ）A．正极发生得电子的氧化反应B．电子通过导线由铜片流向锌片C．正极有O2逸出D．铜片上有H2逸出