Solve the Equation $\left( 3 ^ { x + 5 } \right) \left( 3 ^ { x } \right) = 81$

Solve the equation. $\left( 3 ^ { x + 5 } \right) \left( 3 ^ { x } \right) = 81$

A) $x = \frac { 3 } { 2 }$
B) $x = \frac { 9 } { 2 }$
C) $x = - \frac { 1 } { 2 }$
D) $x = - \frac { 7 } { 2 }$