Which of the following painters was most closely associated with the Ashcan school?

Apparently none.

http://www.artcyclopedia.com/history/ashcan-school.html

The Ashcan School was a group of early 20th-century American artists who sought to depict the grittier, everyday realities of urban life. To determine which painter was most closely associated with the Ashcan School, we can examine the prominent artists associated with this movement and their works.

Here are a few well-known painters associated with the Ashcan School:

1. Robert Henri: Robert Henri was one of the founders and leading figures of the Ashcan School. He believed in capturing the contemporary social realities of New York City and encouraged his students to do the same.

2. George Bellows: George Bellows was an American realist painter who focused on urban scenes, including boxing matches, street scenes, and portraits. He was strongly associated with the Ashcan School.

3. John Sloan: John Sloan was an American artist and illustrator who was active during the early 20th century. He was also considered one of the leading members of the Ashcan School and painted scenes of everyday life in New York City.

By examining the painters associated with the Ashcan School, we can conclude that Robert Henri, George Bellows, and John Sloan were all closely connected to the movement. However, Robert Henri is often considered the most closely associated with the Ashcan School, as he played a significant role in establishing its principles and ideas.