听力原文：

G: William, could you tell me what this is?

B: This is a moving house for one person to live in.

G: Who invented it and when?

B: 16 college students in the United States invented it in 2014.

G: What is it used for doing?

B: The moving house is used for living outside. It can protect the environment, save energy and recycle resources. 

G: Is it made of many new materials?

B: Yes. It has four wheels to move around, a toilet and a small rainwater harvesting system to supply water to the house and a 120-watt solar panel to power the house.

G: What a wonderful invention!

答案: 6. B