This is an authentication method in which is used to prove that a party knows a password without transmitting the password in any recoverable form over a network. This authentication is secure because the password is never transmitted over the network, even in hashed form; only a random number and an encrypted random number are sent.

A.
Realm Authentication

B.
SSL Authentication

C.
Basic Form Authentication

D.
Cryptographic Authentication

E.
Challenge/Response Authentication

Explanation:
Challenge-Response Authentication The secure Challenge-Response Authentication Mechanism (CRAM-MD5) avoids passing a cleartext password
over the network when you access your email account, ensuring that your login details cannot be captured and used by anyone in transit.
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