A block of mass M is kept on a smooth surface and touches the two spring as shown in the figure but not attached to the spring . Initially spring are in their natural length. Now, the block is shifted (l0/2) from the given position in such a way that it compresses a spring and released. The time - period of oscillation of mass will be
(a) (pi/2)√(M/k)
(b) (2pi)√(M/5k)
(c) (3pi/2)√(M/k)
(d) pi√(M/2k)
