1. Gravity: This is the force pulling the body downwards, towards the center of the Earth.

2. Air Resistance (Drag): This force opposes the body's motion, acting in the opposite direction of its velocity. It is dependent on factors like the object's shape, size, and speed.

3. Buoyancy: This force acts upward, due to the displaced air by the falling body. It is generally much smaller than the other forces.

4. Lift: This force acts perpendicular to the direction of motion. While typically associated with airplanes, it can also play a minor role in the case of objects with a specific shape or orientation.

Additional forces might also be present, depending on the specific scenario:

* Thrust: This force would apply if the body is propelled by an engine.

* Magnus Force: This force occurs due to spin, affecting objects like spinning baseballs.

Therefore, the exact number of forces acting on a falling body can vary depending on the situation. However, a minimum of four forces (gravity, air resistance, buoyancy, and lift) are always present.