The correct answer is - the air movement/winds.
The movement of the air, more commonly referred to as winds, is the one responsible for the creation of the waves in the oceans, as well as the seas, and the lakes.
The frictional force from the winds is a force that appears when the moving air influences a certain object/material/substance. Even though the frictional force is lower on smoother surfaces, including the water bodies, it still manages to create surface disruptions on the ocean waters, thus creating the ocean waves.
The stronger this force is, the bigger the waves would be, and vice versa, the lower this force is, the smaller the waves would be.
