Consider a Physical Pendulum Constructed by Attaching a Thin, Massless $500 \mathrm{~g}$

Consider a physical pendulum constructed by attaching a thin, massless rod to the center of a uniform disc of mass $500 \mathrm{~g}$ and radius $4.00 \mathrm{~cm}$ . The disc has a moment of inertia of $1 \frac{1}{2} \mathrm{MR}^{2}$ about an axis perpendicular to the plane of the disc, through its center. With the rod hung from one end (the pivot) , the plane of the disc (attached to the other end) is vertical. If the rod has a length of $50.0 \mathrm{~cm}$ , then the period of (small amplitude) oscillations of the pendulum will be

A) $1.24 \mathrm{sec}$ .
B) $1.74 \mathrm{sec}$ .
C) 2.25 sec.
D) $1.42 \mathrm{sec}$ .
E) $1.90 \mathrm{sec}$