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. German aircraft carrier I (1942) -  The German aircraft carrier I was a planned conversion of the transport ship Europa during World War II. The loss of the battleship Bismarck and near torpedoing of her sistership Tirpitz in May 1941 and March 1942 respectively spurred the Kriegsmarine to acquire aircraft carriers. Europa was one of several vessels selected for conversion into auxiliary aircraft carriers.
The answer is:
Mean Of Transportation