Translate the Verbal Phrase into a Mathematical Expression $\frac { x } { 13 }$

Multiple Choice

Translate the verbal phrase into a mathematical expression. Use x to represent the unknown number.
-The ratio of a number and 13

A) $\frac { x } { 13 }$
B) $13 - \mathrm { x }$
C) $13 + x$
D) $13 x$