The optimal span of control for a management assistant can vary depending on the specific needs of the organization they are working for. Generally, a span of control between 3-10 team members is considered adequate, as it allows for close supervision and effective communication with each person. However, other factors, such as the complexity of tasks, the experience level of the team members, and the overall size of the organization, may also play a role in determining the optimal span of control. Ultimately, a skilled management assistant will be able to adapt their approach to best serve the needs of their team and organization.

The interviewer asks this question to gain insight into your management style and ability to supervise and communicate with a team effectively. Your answer can also demonstrate your understanding of the organization's needs and how you can adapt to meet those needs.