Final answer:
The correct answer to the question is B. In downward direction along inclined plane, as the frictional force acts to prevent the sphere from slipping while it rolls up the inclined plane.
Step-by-step explanation:
The question addresses a sphere rolling up a rough inclined plane and asks about the direction of the frictional force on the sphere. When the sphere rolls without slipping, the frictional force must be opposite to the direction of slipping that would occur if there were no friction.
Therefore, since the sphere is moving up the inclined plane, the frictional force must be acting downwards along the inclined plane to oppose the motion and prevent slipping.
Thus, the mention correct option for the direction of the frictional force acting on a sphere rolling up a rough inclined plane is B. In downward direction along inclined plane.