What Is Mandatory Sign-On? an Authentication Method That

What is mandatory sign-on? An authentication method that:

A) uses smart cards, hardware tokens, and biometrics to authenticate users; also known as three-factor authentication
B) requires the use of one-time passwords, so users authenticate only once, with a given set of credentials
C) requires users to re-authenticate at each server and access control
D) stores user credentials locally, so that users need only authenticate the first time a local machine is used
E) allows users to authenticate once, and then uses tokens or other credentials to manage subsequent authentication attempts