Answer: (B) Accelerated
A passenger in a moving train tosses a coin upward which falls behind him. It implies that the motion of the train is accelerated. It happens because by the time the coin remains in the air, its velocity reduces and it falls behind the passenger.
Acceleration is defined as the rate of change of velocity with respect to time. Acceleration is a vector quantity as it has both magnitude and direction. It is also the second derivative of position with respect to time or it is the first derivative of velocity with respect to time.