Which virtualization model relies on a common host operating system as the base for containers?

• A. Emulation
• B. Container-Based Virtualization
• C. Application Virtualization
• D. Hyper-Converged Infrastructure

Answer: (B)

The concept being tested is OS-level virtualization where multiple containers run on a single host operating system and share its kernel. In this model, containers use the host OS as the base, each with its own isolated user space and processes, but without requiring separate kernel instances for every container. This shared-kernel approach makes containers lightweight, fast to start, and efficient, while still keeping isolation between applications.

This differs from emulation, which runs virtual hardware and separate guest operating systems, adding significant overhead. It also differs from application virtualization, which packages an application and its dependencies but doesn't provide a shared kernel for multiple containers. Hyper-converged infrastructure combines compute, storage, and networking in one system, which is not about the virtualization method used for isolating workloads.

So, container-based virtualization is the model that relies on a common host operating system as the base for containers.