Well if "all of the above" isnt an answer then each answer has a 33.5 percent chance of being correct. So with this information, we know that the emotion comes from yes, the balance of the piece- but more so from contrast. Contrast makes the film, image, art, etc, set the mood, the mood is part of the emotion in the piece of art. Even though, with contrast being important, over all Facial expressions are more of a indicator on what people's emotions are. Facial expressions are things we see in everyday life (except when quarantine happened) and its something we can relate to, and plus there's no mood changing contrast in reality.
