Solve the Problem $\angle x=(200-4 n)^{\circ} \cdot \angle y=(5 n+61)^{\circ} \cdot \angle z=(n+9)^{\circ}$

Multiple Choice

Solve the problem.
-Find the measure of the indicated exterior angle.
$\angle x=(200-4 n) ^{\circ} \cdot \angle y=(5 n+61) ^{\circ} \cdot \angle z=(n+9) ^{\circ}$

A) $144 ^ { \circ }$
B) $122 ^ { \circ }$
C) $148 ^ { \circ }$
D) $128 ^ { \circ }$