The correct answer is D. weighted average conversion cost.
Weighted average conversion cost is calculated by dividing the total cost of conversion for the period by the total equivalent units of conversion for the period. The total cost of conversion includes direct labor and factory overhead. The total equivalent units of conversion are the sum of the units started and completed and the equivalent units of work in process at the end of the period.
The other options are incorrect because they do not take into account the cost of conversion. Gross weighted margin is calculated by dividing the total sales revenue by the total units sold. Weighted average revenue is calculated by dividing the total sales revenue by the total equivalent units of production.
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