When multiple production department rates are used to apply overhead to products, overhead costs are a. combined with all other support department costs using a single rate and then allocated to products with multiple rates. b. first directly traced or distributed to the products using multiple rates. C. expensed as period costs and direct labor and direct materials are traced to the products using multiple production department rates. Od. first directly traced or distributed to support and production departments and then allocated to production departments based on support activity used by each production department