Which two components are core to vSphere? (Choose two.)

Which two components are core to vSphere? (Choose two.)
A . ESXi
B . vSAN
C . vCenter Server
D . vRealize Network Insight
E . vRealize Operations Manager

Answer: A,C

Explanation:

Reference: https://docs.vmware.com/en/VMware-vSphere/6.7/com.vmware.vsphere.vcenterhost.doc/GUID-302A4F73-CA2D-49DC-8727-81052727A763.html