The acceleration due to gravity at the Earth's surface is 9.8 m/s/s
So a 2 kg object will accelerate at 9.8 m/s/s if it is dropped..... actually all dropped objects will accelerate at the same rate.
The force of gravity on the object is given by Newton's 2nd Law
F = m . a
F = 2 . 9.8 = 19.6 N
Now go to Mars , with a lower gravitational field strength. It only accelerates falling objects at 3.71 m/s/s
So the force of gravity on the object is F = 2 . 3.71 = 7.42 N
But the answer is (2) 2 kg, because the mass of the object stays the same and that is what you are asked for.
Someone was trying to be tricky.
