Final answer:
Water waves are caused by wind, which is directly caused by the energy of the sun.
Step-by-step explanation:
Water waves are caused by wind, which is directly caused by the energy of the sun. When the sun heats up the Earth's surface, it creates temperature and pressure differences. The air molecules in the atmosphere move from areas of high pressure to areas of low pressure, creating wind. This wind creates friction with the surface of the water, causing the water to form waves.
Learn more about The relationship between the sun, wind, and water waves