Simplify and Write with Positive Exponents Only $6 z ^ { - 4 }$

Multiple Choice

Simplify and write with positive exponents only.
- $6 z ^ { - 4 }$

A) $\frac { 1 } { 1296 z ^ { 4 } }$
B) - $\frac { 1 } { 1296 z ^ { 4 } }$
C) $\frac { 6 } { z ^ { 4 } }$
D) - $\frac { 1296 } { z ^ { 4 } }$