The correct answer is D. All of the above.
Suspension is a method of transporting particles in a fluid by suspending them in the fluid. The particles are not dissolved in the fluid, but are instead held in suspension by Brownian motion and the viscosity of the fluid.
Solution is a method of transporting molecules in a fluid by dissolving them in the fluid. The molecules are evenly distributed throughout the fluid and are not visible to the naked eye.
Traction is a method of transporting particles in a fluid by dragging them along the surface of the fluid. The particles are in contact with the surface of the fluid and are moved along by the motion of the fluid.
All three of these methods can be used to transport materials within a transporting medium. The method that is used will depend on the properties of the material being transported, the properties of the transporting medium, and the desired outcome of the transport.
For example, suspension is often used to transport large particles or particles that are not soluble in the transporting medium. Solution is often used to transport small particles or particles that are soluble in the transporting medium. Traction is often used to transport particles that are attached to a surface or that are too large to be suspended in the transporting medium.