Final answer:
Marcel Duchamp's L.H.O.O.Q. incorporates a mustache and beard on a postcard of Mona Lisa as a Dadaist act challenging cultural values, with a title that is a wordplay in French signifying sexual excitement.
Step-by-step explanation:
Marcel Duchamp's artwork titled L.H.O.O.Q. is a famous Dada piece where he drew a mustache and beard on a postcard reproduction of Leonardo da Vinci's Mona Lisa. The title L.H.O.O.Q. is a pun that reveals Duchamp's fondness for wordplay. When pronounced in French, it sounds like "Elle a chaud au cul", which is a vulgar expression meaning "There is fire down below", referring to a state of sexual excitement. Duchamp's alteration of the iconic feminine image with a masculine mustache can be seen as a commentary on gender roles. This act of defacing a reproduction of one of the most celebrated paintings in history also served as a challenge to established cultural and artistic values, which was a cornerstone of the Dada movement.