Write the Following Expressions So That No Answer Includes Negative $x ^ { - 13 }$

Multiple Choice

Write the following expressions so that no answer includes negative exponents.Assume the variables are nonzero.
- $x ^ { - 13 }$

A) $- 13 x$
B) $\frac { 1 } { x - 13 }$
C) $\frac { 1 } { { } ^ { 13 } }$
D) $- x ^ { 13 }$
E) None of these