Which of the following sequence represent the process of blood clothing? 1. Fibrin forms a network of threads 2. Red blood cells are caught and a clot is formed 3. Fibrinogen in plasma changes into soluble fibrin 4. Blood is exposed to air.

• A.4,3,2,1
• B.4,3,1,2
• C.3,1,4,2
• D.1,2,3,4