Perform the Indicated Operation $\left( 3 x ^ { 2 } + 4 \right) + \left( 8 x ^ { 2 } + 20 \right)$

Multiple Choice

Perform the indicated operation.
- $\left( 3 x ^ { 2 } + 4 \right) + \left( 8 x ^ { 2 } + 20 \right)$

A) $11 x ^ { 2 } + 16$
B) $11 x ^ { 2 } + 24$
C) $5 x ^ { 2 } + 16$
D) $5 x ^ { 2 } + 24$