ANS:C - complete oscillation

The periodic time of a particle moving with simple harmonic motion is the time taken by the particle for one complete oscillation. In simple harmonic motion (SHM), a particle moves back and forth around an equilibrium position under the influence of a restoring force that is directly proportional to the displacement from the equilibrium position and acts in the opposite direction. The motion repeats itself in a periodic manner. The periodic time, also known as the period T, is the time taken for the particle to complete one full oscillation, starting from a particular point, going to one extreme, returning to the starting point, then reaching the opposite extreme, and finally returning to the starting point again. Therefore, the correct option is: complete oscillation.