A \( \frac{\left ( - 1 \right ) n ! a^{n - 1}}{\left ( a x + b \right )^{n}} \)
B \( \frac{\left ( - 1 \right )^{n - 1} \left ( n - 1 \right ) ! a^{n}}{\left ( a x + b \right )^{n}} \)
C \( \frac{\left ( - 1 \right )^{n - 1} \left ( n - 1 \right ) ! a^{n - 1}}{\left ( a x + b \right )^{n}} \)
D None of these