Which of the following is a type of authentication?

Multifactor authentication is a type of authentication that enhances security by requiring users to provide two or more verification factors to gain access to a resource, rather than just a username and password. This method increases the difficulty for unauthorized users to access systems or sensitive information because it combines something the user knows (like a password), something the user has (such as a smartphone for receiving a verification code), and sometimes something the user is (biometric data like fingerprints).

This layered approach significantly improves security by making it much harder for attackers to compromise an account, as obtaining multiple forms of authentication typically requires more effort and resources.

In contrast, while single sign-on is a convenience feature that allows users to log in once to access multiple services, it is not an authentication method by itself but rather a way to streamline the user experience. Data encryption focuses on securing information by converting it into a format that is unreadable without the appropriate decryption key, and access control involves permissions that restrict or allow users’ abilities to interact with resources but does not in and of itself verify user identities.