Answer:
D) assemble-to-stock operation
Explanation:
In the assembly to stock operations, products are assembled from per-manufactured components upon receipt of a customer order. The company makes the components or the sub-assemblies, or they may be ordered from other manufacturers. The components also called modules are stocked waiting to be manufactured into a final product.
The assembly-to-stock operation reduces customer waiting time once an order has been placed. It also allows for customization of products as per the customer's specifications. The assembly to stock is a hybrid between the make-to-order approach where a product is manufactured only when a customer orders, and make-to-stock where products are fully manufactured in advance.