Is seawater an example of a compound, a homogeneous mixture, an element, or a heterogeneous mixture?

Seawater is an example of b) a homogeneous mixture.

Explanation: Seawater consists primarily of water (H₂O) mixed with various dissolved salts, minerals, and organic materials. While it does contain multiple components, these substances are evenly distributed at a molecular level when seawater is mixed. Because of this uniform distribution, seawater does not have distinct layers or regions and appears consistent throughout, which is characteristic of a homogeneous mixture.