Which of the following protocols is used to validate whether trust is in place and accurate by
returning responses of either “good”, “unknown”, or “revoked”?

A.
CRL

B.
PKI

C.
OCSP

D.
RA

Explanation:
The Online Certificate Status Protocol (OCSP) is an Internet protocol used for obtaining the
revocation status of an X.509 digital certificate.
An OCSP responder (a server typically run by the certificate issuer) may return a signed response
signifying that the certificate specified in the request is ‘good’, ‘revoked’, or ‘unknown’. If it cannot
process the request, it may return an error code.