The earliest form of jazz was ragtime, lively songs or rags performed on the piano, and the best-known of the ragtime performers and composers was Scott Joplin. Bom in 1868 to former slaves, Scott Joplin earned his living from a very early age playing the piano in bars along the Mississippi. One of his regular jobs was in the Maple Leaf Club in Sedalia, Missouri. It was there that he began writing the more than 500 compositions that he was to produce, the most famous of which was “The Maple Leaf Rag.”

The word “which” in paragraph 2 refers to _______.