Simplify the Expression $7 ^ { 2 } r ^ { - 7 } \left( r ^ { 8 } \right) ^ { 5 }$

Multiple Choice

Simplify the expression. Assume that the variable represents a nonzero real number. Write the answer using a positive exponent only. $7 ^ { 2 } r ^ { - 7 } \left( r ^ { 8 } \right) ^ { 5 }$

A) $\frac { 49 } { r ^ { 33 } }$
B) $49 r ^ { 6 }$
C) $7 r ^ { 6 }$
D) $7 r ^ { 47 }$
E) $49 r ^ { 33 }$