જયારે માણસ રફ સપાટી પર ચાલતો હોય તે સ્થિતિ

By Newton's third law of motion, the ground exerts back an equal and opposite force along the line of action of the force we exert on the ground. The vertical component of this reaction force balances our weight (so we do not have any motion perpendicular to the ground), and the horizontal component pushes us forward. So we move

Hence $C$ option is correct