15. Under what circumstance might a certification authority (CA) revoke a certificate?

Вариант ответа 1 - A. The certificate owner has not utilized the certificate for an extended period.

Вариант ответа 2 - B. The certificate owner public key has been compromised.

Вариант ответа 3 - C. The certificate owner’ private key has been compromised.

Вариант ответа 4 - D. The certificate owner has upgraded his/her web browser.