Which of the following is not a clotting factor in blood?

The correct option is D None of the above
The damaged tissue outside the blood vessel activates a cascade of different clotting factors.

Fibrinogen is a proteinacious clotting factor. Fibrins are formed by the conversion of inactive fibrinogens in the plasma by the enzyme thrombin.

Prothrombin is a proteinaceous clotting factor. Prothrombin is the inactive form of thrombin that is always present in the plasma.

Calcium is the non proteinaceous clotting factor. Calcium ions are required for most steps of coagulation.