TACACS+ is specifically designed to handle authentication, authorization, and accounting as separate processes, which provides more control over each individual function. Unlike RADIUS, which combines authentication and authorization, TACACS+ allows administrators to set different levels of access and maintain detailed logs of user activities, making it the correct choice for granular control. SSH, while providing a secure connection, is not an authentication service. EAP is a general framework for authentication and is often used within wireless networks and point-to-point connections, but does not provide the same level of granular control over authorization and accounting as TACACS+.