Final answer:
Vitamin K is vital for blood clotting as it aids in the formation of prothrombin and subsequent clotting factors. Its deficiency can cause bleeding disorders due to increased clotting time and decreased prothrombin levels.
Step-by-step explanation:
The correct answer to the multiple choice question, "Vitamin _____ is vital to the function of certain clotting factors", is Vitamin K. Vitamin K is essential for the synthesis of prothrombin, which is a precursor to thrombin. Thrombin plays a crucial role in the conversion of fibrinogen to fibrin, the protein that forms the structure of blood clots. Vitamin K is also responsible for catalyzing the formation of proconvertin in the liver cells, acting as a coenzyme in the carboxylation of glutamate residues on clotting factors, and participating in the electron transport chain.
Deficiency of Vitamin K can lead to increased clotting time and reduced blood prothrombin levels, resulting in continuous bleeding and other health issues. It's important to note that while Vitamin K is a fat-soluble vitamin and can be consumed through the diet, it is also synthesized by bacteria in the large intestine.