Step 1: Understanding the role of Vitamin K.
Vitamin K plays a crucial role in the coagulation process (blood clotting). It is essential for the synthesis of certain proteins that are required for blood coagulation.
Step 2: Analysis of options.
(A) Vitamin A: Vitamin A is important for vision, immune system function, and cell growth, but it does not directly aid in blood coagulation.
(B) Vitamin D: Vitamin D is essential for calcium metabolism and bone health, not for blood clotting.
(C) Vitamin E: Vitamin E acts as an antioxidant and plays a role in protecting cells, but it does not directly contribute to blood coagulation.
(D) Vitamin K: Correct — Vitamin K is vital for blood coagulation as it activates proteins required for the clotting process.
Step 3: Conclusion.
The correct answer is (D) because Vitamin K is the vitamin responsible for blood coagulation.