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. HMHS Rewa -  HMHS Rewa (His Majesty's Hospital ship) was a steamship originally built for the British-India Steam Navigation Company but requisitioned for use as a British hospital ship during the First World War. On 4 January 1918 she was hit and sunk by a torpedo from the German U-boat U-55.
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Mean Of Transportation