A directional antenna is designed to focus the wireless signal in a specific direction, which makes it the best choice for the described scenario. It concentrates the signal in one particular area, which is ideal for a long corridor. An omni-directional antenna emits a signal in all directions, which would not be as effective in focusing the coverage down the length of the corridor. Sector antennas are also directional but cover a wide angle, typically used for outdoor coverage. A parabolic antenna is highly directional but better suited for long-distance point-to-point communication, not appropriate for a corridor scenario.