Final answer:
The buoyant force acts in the upward direction and is the net upward force on an object in a fluid, according to Archimedes' principle. It opposes the weight of the immersed object and can cause it to float, sink, or remain suspended, depending on whether the buoyant force is greater than, less than, or equal to the object's weight.
Step-by-step explanation:
The correct answer to the question of which is true of the buoyant force is B. It acts in the upward direction. According to Archimedes' principle, the buoyant force is the net upward force exerted on any object that is either wholly or partially immersed in a fluid. This force arises because pressure increases with depth in a fluid, resulting in a greater upward force on the bottom of the object than the downward force on its top. Consequently, the buoyant force opposes the weight of the immersed object, allowing it to experience an upward push.
If the buoyant force is equal to the object's weight, the object will remain suspended at its current depth. If the buoyant force exceeds the weight, the object will rise to the surface and float. On the other hand, if the buoyant force is less than the object's weight, the object will sink. Therefore, the buoyant force does not make an object feel heavier; instead, it can make it appear lighter in a fluid.