阅读下面短文,从各题所给的选项中,选出最佳选项。
Mandy is an English girl. She has a dream one day. In her dream, people's life in the future won't be the same as it is today.
In the dream, Mandy sees many airports on the roof(楼顶). It is easy for people to go to other countries by plane. Mandy also sees many underground stations in the dream. Lots of people take the underground to work or to school. Because the underground runs fast and there's no traffic jam. It helps people save much time.
In Mandy's dream, many people are busy with their work. They don't have lots of time to do exercise. It's difficult to stay healthy. But there is a new way to help people be healthy.
People can take the small exerciseequipment with them and they can exercise everywhere when they want.
Mandy also sees some robots at schools, in shops and at people's homes in her dream. These robots help people do many things. But some people may lose their jobs because of those robots. Their life will be more difficult.
All in all, the new changes in Mandy's dream help people a lot, but not all the changes are good.