their mass their height their weight their volume
I gave my students this multiple choice question: When the first American astronauts were planning to walk on the Moon, they knew that the gravity on the Moon was less than the gravity on Earth. With this information, what did the astronauts expect to be most different on the Moon?

Only one answer is correct among these 4 choices:
- their mass
- their height
- their weight
- their volume

Could you tell me which one is correct?

their weight