Which concept highlights the relationship between buoyancy and the density of fluids?

Archimedes' principle is a fundamental concept in fluid mechanics that explains how buoyancy is directly related to the density of fluids. According to this principle, any object submerged in a fluid experiences an upward buoyant force that is equal to the weight of the fluid that the object displaces. This principle indicates that the buoyant force acting on an object is influenced by the fluid's density; denser fluids will exert greater buoyant forces than less dense fluids when the same volume of fluid is displaced.

For example, if you place a solid object in water, the water will exert an upward force on the object. The amount of this force depends on the water's density. If you were to place the same object in a denser fluid, like saltwater, it would experience an even greater buoyant force owing to saltwater's higher density compared to fresh water. This relationship between buoyancy and fluid density is precisely what Archimedes' principle conveys, making it the correct answer in this context.