Which of the following ensures confidentiality of information sent over the internet?

A.
Digital signature

B.
Digital certificate

C.
Online Certificate Status Protocol

D.
Private key cryptosystem

Explanation:
Confidentiality is assured by a private key cryptosystem. Digital signatures assure data integrity, authentication
and nonrepudiation, but not confidentially. A digital certificate is a certificate that uses a digital signature to bind
together a public key with an identity; therefore, it does not address confidentiality. Online Certificate Status
Protocol (OCSP) is an Internet protocol used for obtaining the revocation status of a digital certificate.