Use the Properties of Exponents to Simplify the Expression $\left. 4 a ^ { 1 / 7 } b ^ { 5 / 7 } \right) ^ { 3 }$

Use the properties of exponents to simplify the expression. Write with positive exponents.
- $\left. 4 a ^ { 1 / 7 } b ^ { 5 / 7 } \right) ^ { 3 }$

A) $4 a ^ { 3 / 7 } b ^ { 15 / 7 }$
B) $64 a ^ { 3 / 7 } b 15 / 7$
C) $64 ( \mathrm { ab } ) ^ { 15 / 7 }$
D) $12 \mathrm { a } ^ { 3 / 7 } \mathrm {~b} ^ { 5 / 7 }$