In a cell topology, an administrative request to start a server is typically managed by the admin service running on the node agent. The node agent serves as an intermediary between the deployment manager and the application servers running on the node. When a request to start a server is initiated, it is sent to the admin service running on the node agent, which then carries out the necessary actions to start the application server. Hence, the correct statement describing an administrative request to start a server in a cell topology is that the request is sent to the admin service running on the node agent.