Final answer:
The role of an account executive is indeed the focal point of agency-client relationships, being responsible for managing and nurturing these interactions within an advertising or marketing agency. The answer is option E.
Step-by-step explanation:
The true statement about the role of an account executive is that E. It is the focal point of agency-client relationships. Account executives are primarily responsible for maintaining and building client relationships within advertising or marketing agencies.
This role involves understanding the client's needs, representing these needs within the agency, coordinating with other departments like creative, media, or research, and ensuring that projects are completed to the client's satisfaction. It does not have an extensive creative aspect as it's more about client service and project management, nor is it considered just a research or subsidiary function.