Which option best describes the process of forming a clot during coagulation?

• A. Osmosis
• B. Fermentation
• C. Diffusion
• D. Clotting

Answer: (D)

Clotting is the body's mechanism for stopping bleeding by forming a clot. During coagulation, platelets and clotting factors work together to convert fibrinogen into fibrin, creating a mesh that traps blood cells and seals the wound. This is precisely what clotting describes in the context of coagulation. The other terms refer to different processes—osmosis is water movement across membranes, diffusion is the spread of molecules from high to low concentration, and fermentation is anaerobic energy production. None of these describe clot formation, so clotting is the correct description of the process.