Factor the Expression by Grouping Terms $3 x ^ { 3 } + x ^ { 2 } - 15 x - 5$

Multiple Choice

Factor the expression by grouping terms. $3 x ^ { 3 } + x ^ { 2 } - 15 x - 5$

A) $\left( x ^ { 2 } - 5 \right) ( 2 x + 1 )$
B) $\left( x ^ { 2 } - 6 \right) ( 3 x + 1 )$
C) $\left( x ^ { 2 } - 6 \right) ( 2 x + 1 )$
D) $\left( x ^ { 2 } + 5 \right) ( 3 x - 1 )$
E) $\left( x ^ { 2 } - 5 \right) ( 3 x + 1 )$