Explanation/Reference:
Explanation:
In a trusted third-party model of federation, each member organization outsources the review and approval task to a third party they all trust. This makes the third party the identifier (it issues and manages identities for all users in all organizations in the federation), and the various member organizations are the relying parties (the resource providers that share resources based on approval from the third party).

All of these answers are actually correct, but A is the best answer, because it is the most general, includes the others, and is therefore the optimum choice. This is a good example of the type of question that can appear on the actual exam.

SaaS most commonly uses client-side key management. With this type of implementation, the software for doing key management is supplied by the cloud provider, but is hosted and run by the cloud customer.
This allows for full integration with the SaaS implementation, but also provides full control to the cloud customer. Although the cloud provider may offer software for performing key management to the cloud customers, with the Infrastructure, Platform, and Desktop as a Service categories, the customers would largely be responsible for their own options and implementations and would not be bound by the offerings from the cloud provider.

Explanation
JavaScript Object Notation (JSON) and Extensible Markup Language (XML) are the most commonly used data formats for the Representational State Transfer (REST) API, and are typically implemented with caching for increased scalability and performance.