An administrator has recently moved all VoIP to a CaaS offering. In order to ensure that VoIP traffic remains separate from the rest of the data traffic, which of the following MUST be done?

A.
All VoIP traffic needs to be VLAN tagged

B.
The CaaS CSP needs to create a new subnet

C.
The CaaS CSP needs to create a private VPN

D.
All VoIP traffic needs to have QoS