Following diseases are caused by the deficiency of which vitamin:
Poor coagulation of blood

Answer

To determine which vitamin deficiency causes poor coagulation of blood, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which vitamin deficiency leads to poor coagulation of blood. Poor coagulation is a medical condition where blood does not clot properly.

2. **Identifying the Condition**: Poor coagulation of blood is often associated with a condition known as hemophilia. Hemophilia is characterized by the inability of blood to clot effectively, leading to excessive bleeding.

3. **Role of Vitamins in Blood Coagulation**: Vitamins play a crucial role in various bodily functions, including blood coagulation. Certain vitamins are essential for the synthesis of proteins that are necessary for blood clotting.

4. **Identifying the Relevant Vitamin**: Among the vitamins, Vitamin K is particularly important for blood coagulation. It is required for the synthesis of clotting factors, including prothrombin, which is essential for the blood clotting process.

5. **Conclusion**: Therefore, the deficiency of Vitamin K leads to poor coagulation of blood.

### Final Answer:
Poor coagulation of blood is caused by the deficiency of **Vitamin K**.

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