The following statements are given for a simple harmonic oscillator:

(a) The force acting is directly proportional to the displacement from the mean position and opposite to it.
(b) Motion is periodic.
(c) Acceleration of the oscillator is constant.
(d) The velocity is periodic.


Choose the correct option from the given ones:
1. (a), (b), (d)

2. (a), (c)

3. (b), (d)

4. (c), (d)