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. British Rail Class 104 -  The British Rail Class 104 diesel multiple units were built by Birmingham Railway Carriage and Wagon Company from 1957 to 1959.The first units ordered were for the London Midland Region with the majority of the class for use in North West of England. Sets were also used in Tyneside replacing the former LNER Tyneside electric units following the de-electrification of the North Tyneside Loop line in 1967 but were themselves made redundant by the opening of the Tyne & Wear Metro in 1980.
A:
Mean Of Transportation