Answer:
(c) On your hand
Step-by-step explanation:
As we know that Second law of Newton's,It states that rate of the change in the linear momentum is known as force.
( P = m v)
m=mass
P= Momentum
v=velocity
The velocity is constant then

Therefore
F= 0
It means that acceleration or de -acceleration of the train is zero.
We can say that train is moving with steady motion,then the coin will return in the hand.
Therefore the answer is C.