The Following Standards for Variable Manufacturing Overhead Have Been Established

The following standards for variable manufacturing overhead have been established for a company that makes only one product:

$\begin{array}{l}\begin{array} { | l | r | } \hline \text { Standard hours per unit of output } & 1.6 \text { hours } \\\hline \text { Standard variable overhead rate } & \$ 11.55 \text { per hour } \\\hline\end{array}\\\text { The following data pertain to operations for the last month: }\\\begin{array} { | l | r | } \hline \text { Actual hours } & 4,900 \text { hours } \\\hline \text { Actual total variable overhead cost } & \$ 58,310 \\\hline \text { Actual output } & 3,000 \text { units } \\\hline\end{array}\end{array}$
-What was the variable overhead efficiency variance for the month?

A) $1,155 unfavourable.
B) $1,190 favourable.
C) $1,190 unfavourable.
D) $1,680 favourable.