根据对话内容，选择合适的选项补全对话。

A. Maybe light bulbs(灯泡) are the most useful inventions. B. What kind of books do you want to borrow? C. Great inventions have changed the world a lot. D. Why do you think so? E. What do you think is the most useful invention?

A：Where are you going, Tony?

B：The library. I want to borrow some books.

A：

B：About inventions. You know I have to prepare for the science lesson.

A： And we humans are really great.

B：That's true. People have made lots of inventions.

A：

B：Sorry，I'm not sure.

A：I don't agree. In my opinion, cars are the most useful.

B：

A：Because I can go anywhere quickly and conveniently in my car.