Which technology allows a single physical server to host multiple virtual machines?

The correct answer is virtualization. This technology allows a single physical server to run multiple virtual machines (VMs) by using a hypervisor. The hypervisor sits between the hardware and the operating system and manages the distribution of physical resources like CPU, memory, and storage among the VMs. Each virtual machine runs its own operating system and applications, effectively allowing different operating environments to coexist on the same physical hardware. This leads to better resource utilization, reduced hardware costs, and increased flexibility in managing and deploying applications.

Containerization, while related, operates differently. It enables lightweight, portable environments for applications to run, but doesn't necessarily provide complete virtual machines with their own operating systems. Instead, containers share the host OS kernel and are built on top of the same infrastructure, focusing more on application-level virtualization.

Segmentation refers to dividing a network into smaller parts for better performance or security, and cloud storage is focused on storing data on remote servers accessed via the internet. Neither directly relates to the capability of hosting multiple operating systems on a single physical server in the way virtualization does.