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. Union Pacific FEF Series - The FEF was a series of three steam locomotive types owned and operated by the Union Pacific Railroad. The classes were: FEF-1; FEF-2; FEF-3. FEF was an acronym for the wheel arrangement four-eight-four.
Answer:
Mean Of Transportation