Which component of a server manages the distribution of physical resources to virtual machines?

The hypervisor is the correct answer because it serves as the virtualization layer that allows multiple virtual machines (VMs) to run on a single physical server. It manages and allocates the physical resources—such as CPU, memory, and storage—of the host server to each VM. This enables efficient resource utilization and isolation between VMs, allowing them to operate independently as if they were separate physical machines.

In virtualization environments, the hypervisor can be either type 1, which runs directly on the hardware, or type 2, which operates atop an existing operating system. In both cases, the hypervisor is essential for ensuring that each virtual machine has access to the resources it needs while also balancing overall system performance.

Other options like the host OS are essential components as well, but they primarily manage the resources for the host machine itself rather than dealing with the distribution to multiple VMs. A resource controller is not a standard term typically used in virtualization; thus it doesn't represent a recognized component dedicated solely to resource management for VMs. A virtual router, while important for networking within virtualized environments, does not directly manage physical resources and instead focuses on routing traffic between virtual networks.