What virtualization capability does ESXi provide to virtual machines?

ESXi provides resource overcommitment as a key virtualization capability. This means that the hypervisor can allocate more virtual resources—such as CPU, memory, and storage—than are physically available on the host machine. This capability enables organizations to maximize their resource utilization by allowing virtual machines to use resources dynamically as needed.

For instance, it's common in virtual environments for many virtual machines to not use their maximum resource allocations at all times. Because of this, ESXi can manage and allocate resources effectively, allowing multiple VMs to share the same physical resources without significant performance degradation. This flexibility allows system administrators to optimize the performance of their workloads and to deploy a higher number of VMs on a given physical server, ultimately leading to improved efficiency and cost savings in IT infrastructure.

Other options, while they describe aspects of virtualization, do not capture the primary function of ESXi in relation to resource management in the way that overcommitment does.