A uniform bar, fixed at one end carries a heavy concentrated mass at the other end. The system is executing longitudinal vibrations. The inertia of the bar may be taken into account by which one of the following portions of the mass of the bar at the free end?

(a) \(\frac{5}{384}\)

(b) \(\frac{1}{48}\)

(c) \(\frac{33}{140}\)

(d) \(\frac{1}{3}\).