they are not the same thing. Osmosis is only for water molecules. i found this, hope it is useful,'Osmosis happens when molecules move from higher to lower concentrations, but diffusion happens when it is reversed'
The answer is d. The kidneys help process your blood and collect all of the waste and extra fluids from it. The bladder helps secrete these wastes and extra fluids from the body and that's why they are apart of the excretory system.
