(a) Common carrier. Travel by common carrier is presumed to be the most advantageous method of transportation and must be used when reasonably available.

(b) Government-furnished automobile. When your agency determines that your travel must be performed by automobile, a Government-furnished automobile is presumed to be the most advantageous method of transportation.

(c) Rental car. If no Government-furnished automobile is available, but your agency has determined that travel must be performed by automobile, then a rental car should be authorized.

(d) Privately Owned Vehicle (POV). POVs should be determined to be the most advantageous method of transportation only after your agency evaluates the use of a common carrier, a Government-furnished automobile, and a rental car.