Which of the following allows a user to authenticate to multiple resources without requiring additional passwords?

MFA (Multi-Factor Authentication) enhances security by requiring users to provide two or more verification factors to gain access to a resource. While it increases security, it does not eliminate the need for multiple passwords; rather, it adds additional steps to the authentication process.

SAML (Security Assertion Markup Language) is a standard for exchanging authentication and authorization data between parties, primarily used for enabling SSO. However, SAML itself does not manage authentication directly; it facilitates SSO implementation, meaning it still relies on SSO capabilities for password-less access among multiple resources.

RADIUS (Remote Authentication Dial-In User Service) is a networking protocol that provides centralized Authentication, Authorization, and Accounting management. While it supports authentication processes, it does not inherently provide the ability to log in to multiple resources without additional credentials; it typically requires passwords for each session.