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. So Cool (Sistar album) -  So Cool is the debut album by Korean girl group Sistar. The album was released on August 9 2011. The song with the same title was used as the promotional song. The album contains 12 songs 5 new songs and a special version of the song Ma Boy released by the sub-unit Sistar19. The album was also released worldwide through iTunes.
The answer is:
Album