what questions is open-ended,

Question

which artist created this piece of art,
do you like to make art,
would you hang this piece of art on your wall,
what makes a piece of art interesting

Answer 1

The open-ended question from your list is: "What makes a piece of art interesting?"

This question invites a variety of responses and encourages deeper thought and discussion, whereas the other questions tend to elicit more specific and straightforward answers.