Factor Completely $50 a ^ { 4 } b - 72 b ^ { 3 }$

Multiple Choice

Factor completely.
- $50 a ^ { 4 } b - 72 b ^ { 3 }$

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