An endogenous chemical agent of disease is

Options

A. Uric acid
B. Protein deficiency
C. Vitamin deficiency
D. Pollutions

Answer

To solve the question "An endogenous chemical agent of disease is," we will analyze the options provided and determine which one qualifies as an endogenous chemical agent.

### Step-by-Step Solution:

1. **Understanding Endogenous Chemical Agents**:
- Endogenous chemical agents are substances that originate from within the organism's own body. They can lead to diseases due to their accumulation or imbalance.

2. **Analyzing the Options**:
- **A. Uric Acid**: Uric acid is a waste product formed from the breakdown of purines, which are found in many foods. It is produced in the body and can accumulate, leading to conditions such as gout, making it an endogenous chemical agent.
- **B. Protein Synthesis**: This is a biological process that occurs in cells to produce proteins. It is not a chemical agent that causes disease but rather a necessary function of living organisms.
- **C. Vitamin Deficiency**: While vitamin deficiencies can lead to diseases, they are not classified as endogenous agents since they result from a lack of external nutrients rather than an internal chemical imbalance.
- **D. Pollution**: Pollution is an external factor and does not originate from within the organism. It is not considered an endogenous agent.

3. **Conclusion**:
- Based on the definitions and analysis of the options, the correct answer is **A. Uric Acid**. It is an endogenous chemical agent that can lead to disease when accumulated in the body.

### Final Answer:
**A. Uric Acid**

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