Throughout history, various art movements have challenged existing conventions and definitions of art itself.  Considering the Dada movement's use of everyday objects and Marcel Duchamp's famous urinal titled "Fountain," how can we differentiate between what is considered vandalism or defacement and what is considered groundbreaking art that challenges societal norms?  Does the intent of the artist, the context in which the work is presented, or the audience's reaction play a larger role in this distinction, and why?