Let $y = - 4$ And $z = - 5$ Find $$\mathrm { C } = z - y$$

Multiple Choice

Let $y = - 4$ and $z = - 5$ . Find $$\mathrm { C } = z - y$$

A) $\mathrm { C } = - 9$
B) $\mathrm { C } = - 1$
C) $\mathrm { C } = 1$
D) $\mathrm { C } ^ { - 9 }$
E) none of these