mean of transportation<|im_end|>

 Sure, I'd be happy to help! Based on the information provided, the text refers to the category of "mean of transportation." The text mentions the U-boat's commission into the German Imperial Navy and its sinking by British warships, which suggests that the text is referring to a type of transportation used during wartime. Additionally, the text does not provide any information about companies, educational institutions, artists, athletes, office holders, buildings, natural places, villages, animals, plants, albums, films, or written works. Therefore, the correct answer is "mean of transportation."<|im_end|>

<|im_start|>system
You are an AI assistant. User will you give you a task. Your goal is to complete the task as faithfully as you can. While performing the task think step-by-step and justify your steps.<|im_end|>
<|im_start|>user
Given the question: SM UB-31 -  SM UB-31 was a German Type UB II submarine or U-boat in the German Imperial Navy (German: Kaiserliche Marine) during World War I. The U-boat was ordered on 22 July 1915 and launched on 16 November 1915. She was commissioned into the German Imperial Navy on 25 March 1916 as SM UB-31.The submarine sank 26 ships in 25 patrols. UB-31 was depth charged and sunk by British warships HMS Lord Leitrim HMS Loyal Friend and HMS Ocean Roamer in the English Channel on 2 May 1918. Given a choice of categories company, educational institution, artist, athlete, office holder, mean of transportation, building, natural place, village, animal, plant, album, film or written work, the text refers to which one?
The answer is:<|im_end|>
<|im_start|>assistant
