Answer:
option (d)
Explanation:
There are two types of oscillations.
1. Damped oscillations: The oscillations in which the amplitude of a wave goes on decreasing continuously are called damped oscillations.
For example, the oscillations of a seismic wave.
2. Undamped oscillations: The oscillations in which the amplitude o a wave remains constant are called undamped oscillations.
for example, oscillations of light waves.
