Which of the following is a method of multi-factor authentication (MFA) offered by Okta?

SMS authentication is a widely recognized method of multi-factor authentication (MFA) offered by Okta. It adds an extra layer of security beyond just the username and password by requiring users to enter a code sent to their mobile devices via SMS. This ensures that even if someone were to obtain a user's password, they would not be able to access the account without also having access to the user's phone to receive the SMS message.

The use of SMS for authentication is particularly effective because it involves something the user possesses (their mobile device), satisfying the typical requirements of MFA which involve two or more different factors: something you know (like a password) and something you have (like a phone receiving a text). This method is straightforward for users to implement and widely supported, helping to mitigate the risks associated with password-only authentication.

Other options, such as single password entry, manual email verification, and image recognition, do not align with the defined methods of MFA as recognized by Okta. Single password entry involves only one factor (the password), which does not fit the MFA criteria. Manual email verification may also require a second step but does not constitute a strong or reliable form of MFA when compared to SMS authentication. Image recognition techniques are generally not classified as MFA but rather