Final answer:
Network and communication services are not typically a value-added service by manufacturers to increase profits, unlike financing or leasing, customer-support call centers, and after-sales maintenance.
Step-by-step explanation:
The option that is not a value-added service provided by a manufacturer to increase profits is D) Network and communication services. This is because typically, network and communication services are more associated with technology and service providers, rather than manufacturers. Manufacturers usually focus on adding value through tangible products and associated services that directly relate to their products, such as financing or leasing, customer-support call centers, and after-sales maintenance.