Given the question: Pick one category for the following text. The options are - company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work. Bird-class patrol vessel - The Bird-class patrol vessel was a class of large patrol boat built for the Royal Navy. There were five in total: Kingfisher Cygnet Peterel Sandpiper and Redpole.The class was designed for patrol and fishery protection tasks in coastal and inshore territorial waters.
The answer is:
Mean Of Transportation