Final answer:
The main role of a functional manager is to control resources within a specific department or area of a company. Therefore, the correct option is E.
Step-by-step explanation:
The main role of a functional manager is to control resources. Functional managers are responsible for overseeing a specific area within a company, such as marketing, finance, or human resources. They have the authority to allocate resources, make decisions, and ensure that the department is effectively utilizing its resources to meet organizational objectives.