Explanation
A community cloud model is where customers that share a certain common bond or group membership come together to offer cloud services to their members, focused on common goals and interests.

No matter what kind of application, system, or hosting model used, encryption is 100 percent dependent on encryption keys. Properly securing the keys and the exchange of them is the biggest and most important challenge of encryption systems.

Explanation/Reference:
Explanation:
With SaaS providing a fully functioning application that is managed and maintained by the cloud provider, cloud customers incur the least amount of support responsibilities themselves of any service category.

Explanation
Dynamic resource scheduling (DRS) is used within all clustering systems as the method for clusters to provide high availability, scaling, management, and workload distribution and balancing of jobs and processes. From a physical infrastructure perspective, DRS is used to balance compute loads between physical hosts in a cloud to maintain the desired thresholds and limits on the physical hosts.

Explanation
The use of subcontractors can add risk to the supply chain and should be considered; trusting the provider's management of their vendors and suppliers (including subcontractors) is important to trusting the provider.
Conversely, the customer is not likely to be allowed to review the physical design of the datacenter (or, indeed, even know the exact location of the datacenter) or the personnel security specifics for the provider's staff.
"Redundant uplink grafts" is a nonsense term used as a distractor.