Final answer:
The best time to inform customers about extended service plans is early in the sales process as a benefit to the product being purchased.The correct option is D.
Step-by-step explanation:
The best time to inform customers about extended service plans for items they are purchasing is early in the sales process as a benefit to the product being purchased. This allows customers to consider the value and benefits of the extended services as they make their purchase decision. By presenting the extended service plans at the beginning of the sales process, customers can fully understand the options available to them and how the plans can enhance their overall experience with the product.