Factor X is produced by

Options

A. injured endothelium
B. damaged tissues
C. liver
D. spleen

Answer

### Step-by-Step Solution:

1. **Understanding Factor X**: Factor X is a crucial component in the blood coagulation process. It is involved in the cascade that leads to the formation of a blood clot, which is essential for preventing excessive bleeding when injuries occur.

2. **Identifying the Source of Production**: The question asks where Factor X is produced. The options given are:
- A) Injured endothelium
- B) Damaged tissues
- C) Liver
- D) Spleen

3. **Evaluating Each Option**:
- **A) Injured endothelium**: While the endothelium can release various factors during injury, it does not produce Factor X.
- **B) Damaged tissues**: Similar to the endothelium, damaged tissues can release signaling molecules but do not synthesize Factor X.
- **C) Liver**: The liver is known to synthesize several clotting factors, including Factor X. This is the correct answer.
- **D) Spleen**: The spleen plays a role in filtering blood and immune response but does not produce Factor X.

4. **Conclusion**: Based on the evaluation, the correct answer is C) Liver, as it is the organ responsible for the synthesis of Factor X, which is essential for blood coagulation.