Assertion (a) : A particle of mass m dropped into a hole made along the diameter of the earth from one end to another and possess simple harmonic mention. Reason (R) : Gravitational force between any two particles is inversely proportional to the square of the distance between them.

Question

(a) Both (A) and (R) are true and (R) is the correct explanation of (A)

(b) Both (A) and (R) are true but (R) is not the correct explanation of (A)

(c) (A) is true and but (R) is false

(d) (A) is false but (R) is true