The lobby of the hotel allows users to plug in their laptops to access the Internet. This network is
also used for the IP based phones in the hotel lobby. Mike, the security engineer, wants to secure
the phones so that guests cannot electronically eavesdrop on other guests. Which of the following
would Mike MOST likely implement?

A.
VLAN

B.
Port security

C.
MPLS

D.
Separate voice gateway