The 3 main river systems in the middle east are <span> ,the Tigris, Euphrates, and Nile</span> because middle east is the mountainous and the hilly and the large area of it contain deserts and its major cities and town located on river So in my opinion opinion D is correct
Gravitational tidal heating is stronger on Io than any other moon in the Solar System, providing a source of heat that causes its high level of geological activity.