A cantilever beam oflength L is subjected to a concentrated load P at a distance of L/3 from the free end. The deflection at the free end is

A

$$\frac{1}{3}\frac{PL^3}{EI}$$

B

$$\frac{14}{81}\frac{PL^3}{EI}$$

C

$$\frac{7}{18}\frac{PL^3}{EI}$$

D

$$\frac{1}{2}\frac{PL^3}{EI}$$