CRL
https://ru.wikipedia.org/wiki/Certificate_Revocation_List
Certificate Revocation List (or CRL) is "a list of digital certificates that have been revoked by the
issuing certificate authority (CA) before their scheduled expiration date and should no longer be
trusted".
Incorrect answers:
RA - Used to proxy the certificate requests on behalf of the user and validate whether or not they are
legitimate instead of having the user go directly to the CA. The RA talks to the subordinate CA on
behalf of the user, which makes it harder for the actor to get directly to the certificate authority and
do harm.
RFC – Request for Comments (RFC) is a publication from the Internet Society (ISOC) and its
associated bodies, most prominently the Internet Engineering Task Force (IETF), the principal
technical development and standards-setting bodies for the Internet.
CA - certificate authority or certification authority is an entity that issues digital certificates