A heavy ball of mass M is suspended from the ceiling of a car by a light string of mass m `(m< < M)`. When the car is at rest, the speed of transverse waves in the string is `60 ms^(-1)`. When the car has acceleration a, the wave-speed increases to `60.5 ms^(-1)`. The value of a, in terms of gravitational acceleration g, is closest to

Options

A. `frac(g)(30)`
B. `frac(g)(5)`
C. `frac(g)(20)`
D. `frac(g)(10)`