A. VMFS5 is no longer supported with ESXi 7.0.
B. VMFS3 is no longer supported with ESXi 7.0.
C. An ESXi 7.0 host can automatically upgrade a VMFS5 datastore.
D. An ESXi 7.0 host will automatically upgrade a VMFS3 datastore when discovered.
E. A VMFS3 datastore cannot be upgraded; a new VMFS6 datastore is required.
Explanation: https://docs.vmware.com/en/VMware-vSphere/7.0/com.vmware.vsphere.storage.doc/GUID-DAD74662-E09E-44A4-82F1-DB7A3433CEF9.html