Ingredient A12H Is a Material Used to Make Calvin Corporation's

Ingredient A12H is a material used to make Calvin Corporation's major product. The standard cost of Ingredient A12H is $23.00 per ounce and the standard quantity is 3.8 ounces per unit of output. Data concerning the compound for October appear below:
$\begin{array}{lr} \text {Cost of material purchased in October } & \text { \$23.10per ounce } \\ \text {Material purchased in October } & \text { 2,300 ounces} \\ \text { Material used in production in October } & \text { 2,120 ounces} \\ \text { Actual output in October } & \text { 600 units} \\\end{array}$

The material was purchased on account and Calvin Corporation uses a standard costing system.
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The Material Efficiency Variance for October would be recorded as a:

A) credit of $3,680.
B) debit of $4,140.
C) credit of $4,140.
D) debit of $3,680.