less mass and weight. less mass but equal weight. equal mass but less weight. equal mass and weight.
I gave my students this multiple choice question: An exploratory robot was sent to the planet Mars. The gravity on Mars is weaker than the gravity on Earth. Compared to the mass and weight of the robot on Earth, the robot on Mars has

Only one answer is correct among these 4 choices:
- less mass and weight.
- less mass but equal weight.
- equal mass but less weight.
- equal mass and weight.

Could you tell me which one is correct?

equal mass but less weight.