Which of the following statement are correct -

Options

A. friction acting on a cylinder without sliding one on a inclinded surface is always upward along the incline irrespective of any external force acting on it.
B. friction acting on acylinder without sliding on an inclined surface is may be upward may be downwards depending on the external force acting on it.
C. friction acting on a cylinder rolling without sliding may be zero depending on the external force acting in it.
D. nothing can be said exactly about it as it depends on the friction coefficient on inclined plane.

Answer

B, C