Final answer:
CAT6 cable is the most suitable choice for connecting a PoE enabled phone at 55 meters from the switch because it supports long distances up to 100 meters for both data and power over Ethernet.
Step-by-step explanation:
The most suitable cable type for connecting a PoE (Power over Ethernet) enabled phone at a distance of 55 meters from the switch would be CAT6 cable. CAT6 cables are designed to support Gigabit Ethernet data rates and are capable of providing power over Ethernet up to 100 meters, which well exceeds the 55 meters required for the phone. Unlike fiber optic cables, which excel at long-distance data transmission, or coaxial cables, which are primarily used for television signals and internet service to homes, CAT6 is tailored for network communications and is a standard for modern Ethernet installations providing both data and power in office and voip phone setups. CAT3, on the other hand, is an outdated standard and doesn't support modern networking speeds or PoE requirements.