\(M.I. = \sum {m\,{r^2}} \)
Now, bending of rod does not alter the distribution of individual particle, the body
is made of, so the value of \(\sum {m\,{r^2}} \) will not change. Hence the changed moment of inertia of the body will be \(\frac{1}{{12}}\,\,M{L^2}\)