单项选择题
W: When was the first computer built
M: It was built in 1944.
W: Is it the same as the computers that we use now
M: No, it was as large as a room and very slow.
W: But computers have become smaller and faster now.
M: Yes. Most computers are as small as a TV set, and some are even smaller than a book.
W: Why is a computer so useful
M: It can keep much information and work very fast.
W: Then they can do a lot of work for us.
M: You’re right. They have greatly changed our lives.
A. It becomes smaller.
B. It works faster.
C. Both A and B.
D. It works as fast as the original one.