$ \quad$ A load $P$ is applied to the free end of a stepped cantilever beam as shown in the figure. The Young's modulus of the material is $E,$ and the moments of inertia of the
two sections of length $2 \mathrm{~m}$ and $1 \mathrm{~m}$ are $I$ and $3 I$, respectively. Ignoring transverse shear and stress concentration effects, the deflection at the point where the load is applied at the free end of the cantilever is
(A) $\frac{23}{243 E I}$
(B) $\frac{1}{3 E I}$
(C)$\frac{43}{3 E I}$
(D) $\frac{23}{3 E I}$
$ \quad$ A load $P$ is applied to the free end of a stepped cantilever beam as shown in the figure. The Young's modulus of the material is $E,$ and the moments of inertia of the
two sections of length $2 \mathrm{~m}$ and $1 \mathrm{~m}$ are $I$ and $3 I$, respectively. Ignoring transverse shear and stress concentration effects, the deflection at the point where the load is applied at the free end of the cantilever is
(A) $\frac{23}{243 E I}$
(B) $\frac{1}{3 E I}$
(C)$\frac{43}{3 E I}$
(D) $\frac{23}{3 E I}$