C

Step 1: Understand the motion of a simple pendulum. The acceleration of the pendulum bob can be analyzed in terms of two components: tangential acceleration and centripetal acceleration.
Step 2: The tangential acceleration, which acts along the path of motion, is due to the gravitational component acting on the bob. It is directed towards the equilibrium position when the bob is displaced.
Step 3: The centripetal acceleration is directed towards the center of the circular path and acts perpendicular to the displacement of the bob.
Step 4: For small angles, the combination of these two accelerations results in a net acceleration vector that points towards the center along the angle of displacement.
Looking at the options, the correct representation of this scenario is depicted in option C, where the acceleration vector correctly points towards the pivot based on the displacement of the pendulum bob. Therefore, the correct answer is C.