A router has a single Ethernet connection to a switch. In the router configuration, the Ethernet interface has three sub-interfaces, each configured with ACLs applied to them and 802.1q trunks. Which of the following is MOST likely the reason for the sub-interfaces?
A. The network uses the subnet of 255.255.255.128.
B. The switch has several VLANs configured on it.
C. The sub-interfaces are configured for VoIP traffic.
D. The sub-interfaces each implement quality of service.