Which vitamin is essential for blood clotting?

Vitamin K is essential for blood clotting because it plays a crucial role in the synthesis of certain proteins, known as clotting factors, which are necessary for the blood coagulation process. Without adequate levels of vitamin K, the body cannot effectively form clots, leading to increased bleeding and an inability to stop hemorrhages. This vitamin is found in various foods, such as leafy green vegetables, and is also produced by bacteria in the intestines.

The other vitamins listed do not have a primary role in blood clotting. Vitamin A is important for vision and immune function, Vitamin D is essential for calcium absorption and bone health, and Vitamin C is vital for the growth and repair of tissues and the production of collagen. None of these vitamins are involved in the clotting process to the extent that vitamin K is.