Determine the Integral by Making an Appropriate Substitution $\int \frac { x } { \left( 7 x ^ { 2 } + 3 \right) ^ { 5 } }$

Multiple Choice

Determine the integral by making an appropriate substitution.
- $\int \frac { x } { \left( 7 x ^ { 2 } + 3 \right) ^ { 5 } }$ dx

A) - $\frac { 7 } { 3 \left( 7 x ^ { 2 } + 3 \right) ^ { 6 } }$ + C
B) - $\frac { 1 } { 14 \left( 7 x ^ { 2 } + 3 \right) ^ { 6 } }$ + C
C) $\frac { 7 } { 3 \left( 7 x ^ { 2 } + 3 \right) ^ { 4 } } + C$
D) - $\frac { 1 } { 56 \left( 7 x ^ { 2 } + 3 \right) ^ { 4 } }$ + C