According to theAWS Shared Responsibility Model, AWS is responsible for thesecurity of the cloud, while customers are responsible for thesecurity in the cloud. AWS responsibilities include protecting the physical infrastructure that supports AWS services, such as data centers, hardware, networking, and global infrastructure.

Specifically, AWS is responsible forthe compute infrastructure, which includes servers, storage devices, networking equipment, and virtualization layers. AWS is also responsible forAvailability Zones, ensuring they are physically separate, fault-isolated, and highly available.

Client-side data encryption, Amazon EC2 guest operating systems, and customer data are explicitly defined ascustomer responsibilities. Customers must manage operating system patching, encryption methods, access controls, and data protection within their AWS environments.

AWS documentation consistently emphasizes that customers retain ownership and control of their data, while AWS ensures the resilience, availability, and security of the underlying cloud infrastructure. Therefore, the correct answers areC and D.