What is overcommitting memory in the context of virtualization?

Overcommitting memory in virtualization refers to the practice of allocating more physical RAM to virtual machines (VMs) than what is actually available on the host system. This is often done to optimize resource utilization, as virtualization allows for the possibility that not all allocated memory will be used simultaneously by the VMs.

In a virtualized environment, many VMs can be running concurrently, and it's not uncommon for them to require less memory at different times than what is allocated to them. Thus, by overcommitting memory, system administrators can take advantage of the fact that not all workloads will demand their full allocated memory at once. This strategy can lead to more efficient use of physical resources, but it must be managed carefully to avoid performance degradation. If memory demand exceeds supply, it can lead to swapping and other issues that negatively affect VM performance.

Therefore, option C accurately describes overcommitting memory in the context of virtualization by focusing on the aspect of allocation exceeding available physical RAM.