Microsoft Entra Identity and Access Management (formerly known as Azure Active Directory or Azure AD) is the correct answer because it offers a broad set of identity and access management capabilities, including single sign-on, multi-factor authentication, and conditional access policies, which are essential for securing access to Azure services. Microsoft Entra Permissions Management deals with governance and permissions across various Azure services, not directly with identities. Azure Service Bus is a messaging service and does not handle identity management. Azure Resource Manager is the deployment and management service for Azure resources, not a directory service.