Concept:Buoyancy is the upward force exerted by a fluid on any object immersed in it, as explained by Archimedes' principle.
Explanation:Archimedes' principle states that an object submerged in a fluid experiences an upward force equal to the weight of the fluid displaced by the object.
This upward force is called the buoyant force or buoyancy.
The weight of an object acts downward due to gravity, while the buoyant force acts upward, opposing the weight.
Buoyancy enables objects to float or rise in a fluid when the buoyant force is greater than or equal to the object’s weight.
Thus, buoyancy is specifically an upward force, not a pressure or a downward force.
Hence, the correct choice is "Upward force".
Answer:D. Upward force
