Use the Laws of Exponents to Simplify Each Expression Using $$\left( x ^ { - 6 } \right) ^ { - 3 }$$

Multiple Choice

Use the laws of exponents to simplify each expression using positive exponents only. Assume all variables represent nonzero real numbers.
- $$\left( x ^ { - 6 } \right) ^ { - 3 }$$

A) $\frac { 1 } { x ^ { 9 } }$
B) $- x ^ { 9 }$
C) $\times ^ { 18 }$
D) $\frac { 1 } { \mathrm { x } ^ { 18 } }$