What describes a virtualization type applied by a host OS to provide an isolated execution environment for an application?

• A. Containerization
• B. Multitenancy
• C. Public Cloud
• D. Private Cloud

Answer: (A)

Containerization is OS-level virtualization that creates isolated execution environments for applications by using the host operating system's features. Each container runs in its own isolated user space with its own filesystem, libraries, and settings, but shares the host kernel. This provides separation between applications while keeping overhead low, so containers start quickly and use resources efficiently. This approach differs from multitenancy, which is about multiple users sharing the same software environment rather than isolating an application's runtime. It also differs from public or private cloud, which describe deployment locations and management models rather than the isolation mechanism itself.