Factor the Four-Term Polynomial by Grouping $x ^ { 3 } + 3 x ^ { 2 } + x + 3$

Multiple Choice

Factor the four-term polynomial by grouping.
- $x ^ { 3 } + 3 x ^ { 2 } + x + 3$

A) $\left( x ^ { 2 } + 3 \right) ( x + 1 )$
B) $\left( 3 x ^ { 2 } + 3 \right) ( x + 1 )$
C) $\left( x ^ { 2 } + 1 \right) ( x + 3 )$
D) $\left( x ^ { 2 } + 1 \right) ( 3 x + 3 )$