default or selected kernelversion does not have config value CONFIG_KVM_HYPERV.
Result is shown for kernelversion 6.8-rc6

Support for Microsoft Hyper-V emulation

configname: CONFIG_KVM_HYPERV

Linux Kernel Configuration
└─>Virtualization
└─>Support for Microsoft Hyper-V emulation
Provides KVM support for emulating Microsoft Hyper-V. This allows KVM
to expose a subset of the paravirtualized interfaces defined in the
Hyper-V Hypervisor Top-Level Functional Specification (TLFS):
https://docs.microsoft.com/en-us/virtualization/hyper-v-on-windows/reference/tlfs
These interfaces are required for the correct and performant functioning
of Windows and Hyper-V guests on KVM.

If unsure, say "Y".