Which vSphere action is a prerequisite for creating an external network?

Which vSphere action is a prerequisite for creating an external network?

A.
Create a vSphere Port Group.

B.
Create a vSphere Port Group with VLAN Trunking

C.
Create a vSphere Uplink Port Group.

D.
Create a vSphere Uplink Port Group with VLAN Trunking.