A company wants to ensure that all credentials for various systems are saved within a central database so that
users only have to login once for access to all systems. Which of the following would accomplish this?

A.
Multi-factor authentication

B.
Smart card access

C.
Same Sign-On

D.
Single Sign-On

Explanation:
Single sign-on means that once a user (or other subject) is authenticated into a realm, re-authentication is not
required for access to resources on any realm entity. Single sign-on is able to internally translate and store
credentials for the various mechanisms, from the credential used for original authentication.