Write with Positive Exponents $16 ^ { - 3 / 2 }$

Multiple Choice

Write with positive exponents. Simplify if possible.
- $16 ^ { - 3 / 2 }$

A) $- 64$
B) $\frac { 1 } { 64 }$
C) $- \frac { 1 } { 64 }$
D) 64