The coefficient of x

(d) $-330 m^{7}$

Let $x^{-3}$ occur at $(r+1)$ th term in the given expansion.

Then, we have

$T_{r+1}={ }^{11} C_{r} x^{11-r}\left(\frac{-m}{x}\right)^{r}$

$=(-1)^{r} \times{ }^{11} C_{r} m^{r} x^{11-r-r}$

For this term to contain $x^{-3}$, we must have

$11-2 r=-3$

$\Rightarrow r=7$

$\therefore$ Required coefficient $=(-1)^{7}{ }^{11} C_{7} m^{7}$

$=-\frac{11 \times 10 \times 9 \times 8}{4 \times 3 \times 2} m^{7}$

$=-330 m^{7}$