Factor the Four-Term Polynomial by Grouping $20 a ^ { 3 } + 15 a ^ { 2 } b + 24 a b ^ { 2 } + 18 b ^ { 3 }$

Multiple Choice

Factor the four-term polynomial by grouping.
- $20 a ^ { 3 } + 15 a ^ { 2 } b + 24 a b ^ { 2 } + 18 b ^ { 3 }$

A) $\left( 20 a ^ { 2 } + 6 b ^ { 2 } \right) ( a + 3 b )$
B) $\left( 5 a ^ { 2 } - 6 b ^ { 2 } \right) ( 4 a - 3 b )$
C) $\left( 5 a ^ { 2 } + 6 b \right) ( 4 a + 3 b )$
D) $\left( 5 a ^ { 2 } + 6 b ^ { 2 } \right) ( 4 a + 3 b )$