What type of currents result from the gravitational pull of the sun and moon?

Tidal currents are the correct answer because they are specifically driven by the gravitational pull exerted by the moon and the sun on Earth's waters. These currents are characterized by the regular rise and fall of sea levels, which occur in a predictable pattern due to the alignment of these celestial bodies. When the gravitational forces of the sun and moon interact with Earth's rotation, they create tidal forces that lead to the movement of water in and out of coastal areas, resulting in flooding and ebbing movements of tides.

Wind currents, on the other hand, are generated by the atmospheric conditions and the wind blowing across the surface of the water. Surface currents are primarily driven by these wind patterns and the Earth's rotation, often influenced by the Coriolis effect. River currents, while they do involve movement of water, are related to the flow of freshwater in rivers and streams, rather than the influence of gravity from the sun and moon. Therefore, tidal currents are the only type specifically associated with the gravitational forces from celestial bodies.