A concentrated load is applied at the end of a cantilever as shown in Fig. The cross section of the beam is a square of side ‘a’ with a hole of dia ‘$$\frac{a}{2}$$’. The deflection at the tip of the cantilever is given by

A

$$\frac{3P}{E} \frac{L^{3}}{a^{4}}$$

B

$$\frac{1024P}{(256-3 \pi) E} \frac{L^{3}}{a^{4}}$$

C

$$\frac{1024P}{\left(256-\frac{\pi}{64}\right)E} \frac{L^{3}}{a^{4}}$$

D

$$\frac{256P}{(1024-3 \pi) E} \frac{L^{3}}{a^{4}}$$