Which of the following authentication methods is used to enable a Web browser to provide credentials when making a request during an HTTP transaction?

Anonymous authentication requires no credentials at all, granting access without prompting the browser for a username or password.

Basic Authentication is defined in RFC 7617 and causes the browser to present a credential dialog, then send the username and password encoded in Base64 within the HTTP Authorization request header. It is the simplest and most widely supported method for browsers to supply credentials during an HTTP transaction, though it offers no encryption on its own.

Digest Authentication uses an MD5 hash challenge-response mechanism rather than directly transmitting credentials, making it a different protocol from the one that simply enables browsers to provide credentials.

Integrated Windows Authentication uses Kerberos or NTLM tickets negotiated through the Windows security subsystem, not a generic browser credential prompt suitable for all HTTP clients.