Task: Text Categorization
Input (English): Context: German submarine U-18 was a Type IIB U-boat of Nazi Germany's Kriegsmarine during World War II. It was laid down 10 July 1935 and commissioned on 4 January 1936. It served in many U-boat flotillas during its service.
Question: The document can be classified to which topic? 
Options: 1)Animal, 2)MeanOfTransportation, 3)Building, 4)Artist
Output (English): 2