Given the 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. SS Libau - The Libau (pronounced [lba]; also known as SS Castro) was a merchant steam ship. In 1916 it masqueraded under the cover name of Aud ([ad]) in an attempt to carry arms to Ireland as part of the preparation for the Easter Rising.
The answer is:
Mean Of Transportation