Which of the following enables an organization to leverage an identity provider to manage access...

SSO (Single Sign-On) allows an organization to use an identity provider (IdP) to centrally manage authentication and access across multiple SaaS applications. In the Network+ (N10-009) objectives, identity and access management concepts include federated authentication, centralized account control, and reducing password sprawl. With SSO, users authenticate once to the IdP, and the IdP then provides assertions/tokens to SaaS services (commonly using federation standards such as SAML or OIDC in real environments). This improves security (fewer reused passwords, easier MFA enforcement), streamlines user experience, and simplifies administration (provisioning/deprovisioning from one place).

PKI supports certificates and encryption/signing, but it is not the core mechanism for managing access across many SaaS apps via an IdP. TACACS+ is typically used for device administration (AAA) on network equipment, and RADIUS commonly supports network access (802.1X, VPN) AAA—both are important AAA protocols but do not describe the SaaS-wide “one login across many apps” capability. Therefore, SSO is the best answer.

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