Please answer the following 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. Katsonis-class submarine - The Katsonis class was a French-built class of two submarines for the Hellenic Navy serving from 192728 until the Second World War. The ships of the class were the first new submarines acquired by Greece after the First World War.
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Mean Of Transportation