One end of an elastic string of natural length / and modulus X is kept fixed while to the other end is attached a particle of mass m which is hanging freely under gravity. The particle is pulled down vertically through a distance x, held at rest and then released. The motion is
A
a simple harmonic motion
B
a rectilinear motion with constant speed
C
a damped oscillatory motion
D
none of the above
Correct Answer: a simple harmonic motion