Thank you for reporting, we will resolve it shortly
Q.
In projectile motion power of the gravitational force :
Work, Energy and Power
Solution:
As the projectile goes up power of gravitational force is negative as displacement is opposite to the force and when it comes down it becomes positive and at the topmost point as velocity is normal to weight it is zero. Magnitude of power can be given as $P=m g \cdot v_{y}=m g\left(u_{y}-g t\right)$ hence options (B) and (C) are correct.