The answer is "3). It appears to have been created to mark the unification of Egypt."
It isn't 1, as the Palette of Narmer is an Egyptian artwork, not Sumerian. It isn't 2, as it doesn't feature cuneiform, but hieroglyphs. It isn't 4, as the art isn't Mesopotamian, but Egyptian.
Art is not valued is because it is not accessible. It is treated not as a part of life, but as a non-essential feature of life, reserved for the few, but not for everyone.
