The force exerted by the floor of an elevator on the foot of a person standing there is more than the weight of the person if the elevator is
In general the normal reaction .
But when the elevator is going up, a pseudo force acts in the down direction, thus we get,
If the elevator is slowing down, , sign of a changes.
If the elevator is speeding up,
Thus, option B is correct.
But when the elevator is going down, a pseudo force acts in the up direction, thus we get,
If the elevator is slowing down, , sign of a changes.
If the elevator is speeding up,
Thus, option C is correct.
∴ option B and C are correct.