Concept:Factory wages are direct labour costs linked to the production of goods.Explanation:Prime cost is the total of all direct production costs.The formula is Primecost=Directmaterials+Directlabour+Directexpenses.Factory wages are paid to workers who directly make the product.Therefore, factory wages are classified as direct labour.Since direct labour is a component of prime cost, factory wages belong to prime cost.Answer:D. prime cost