which statement is correct?

You want to implement an IPsec VPN on an SRX device using PKI certificates for
authentication. As part of the implementation, you are required to ensure that the certificate
submission, renewal, and retrieval processes are handled automatically from the certificate
authority. Regarding this scenario, which statement is correct?

A.
You can use SCEP to accomplish this behavior.

B.
You can use OCSP to accomplish this behavior.

C.
You can use CRL to accomplish this behavior.

D.
You can use SPKI to accomplish this behavior.