在有机物分子中，若某个碳原子连接着四个不同的原子或原子团，则这个碳原子被称为“手性碳原子”。凡是只有一个手性碳原子的物质一定具有光学活性，物质

有光学活性，发生下列反应后无光学活性的是(　　)

A．与新制的Cu(OH)₂作用

B．与乙酸发生酯化反应

C．与NaOH水溶液共热

D．在催化剂存在下与H₂加成

根据首字母完成短文

We live in the “computer a 小题1: ”. People, such as scientists, teachers, writers and students, use computers to do all k 小题2:  of work. But more than 30 years ago, computers couldn’t do  m 小题3: . They were very big and expensive. Few people were i 小题4:  in them or knew how to use them. Today computers are smaller and c 小题5: . Since they can do lots of work, many people like to use them. Some people even have them at home. Computers became very important, because they can work faster than men and make f 小题6:  mistakes. They can help people do a lot of things. W 小题7:  now use computers to write, teachers use them to help teaching, students use them to help study, and children use them to play g 小题8: . Computers are very u 小题9: and helpful. They are our good friends. Do you want to o 小题10:  a computer?