
Explanation:

Box 1:
* Token - A user gains access to an RP application by presenting a valid token that was issued by an authority that the RP application trusts.
* Identity Provider (IP) - An authority that authenticates user identities and issues security tokens, such as Microsoft account (Windows Live ID), Facebook, Google, Twitter, and Active Directory. When Azure Access Control (ACS) is configured to trust an IP, it accepts and validates the tokens that the IP issues. Because ACS can trust multiple IPs at the same time, when your application trusts ACS, you can your application can offer users the option to be authenticated by any of the IPs that ACS trusts on your behalf.
Box 2: WS-Trust is a web service (WS-*) specification and Organization for the Advancement of Structured Information Standards (OASIS) standard that deals with the issuing, renewing, and validating of security tokens, as well as with providing ways to establish, assess the presence of, and broker trust relationships between participants in a secure message exchange. Azure Access Control (ACS) supports WS-Trust 1.3.
Incorrect: ACS does not support Kerberos.
References: