The Security Assertion Markup Language (SAML) is the most widely used method for encoding and sending attributes and other information from an identity provider to a relying party.WS-Federation, which is used by Active Directory Federation Services (ADFS), is the second most used method for sending information to a relying party, but it is not a better choice than SAML. XML is similar to SAML in the way it encodes and labels data, but it does not have all of the required extensions that SAML does. HTML is not used within federated systems at all.

With a federated identity system, a user will perform authentication with their home organization, and the application will accept the authentication tokens and user information from the identity provider in order to grant access. The purpose of a federated system is to allow users to authenticate from their home organization.
Therefore, using the application or a third-party authentication system would be contrary to the purpose of a federated system because it necessitates the creation of additional accounts. The use of a cloud provider would not be relevant to the operations of a federated system.

Explanation
The recovery service level (RSL) is a percentage measure of the total typical production service level that needs to be restored to meet BCDR objectives in the case of a failure.