Exam CSCP topic 1 question 100 discussion

Moving the customer decoupling point from finished goods to components is a strategy that can significantly reduce inventory investment while maintaining customer service levels. The customer decoupling point refers to the point in the supply chain where a product is differentiated to meet specific customer requirements. By moving the customer decoupling point from finished goods to components, the company can delay the final assembly of products until customer orders are received. This allows the company to reduce the amount of finished goods inventory it needs to carry, as it can assemble the products based on actual demand.

Moving the customer decoupling point closer to the customer and further upstream in the supply chain involves keeping components or subassemblies in inventory until a customer order is received.

Please why is D the answer here?