Synthesis of urea from ammonia takes place in:

Options

A. kidney
B. blood
C. renal tubules
D. liver

Explanation

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks where the synthesis of urea from ammonia occurs in the body.

2. **Identifying Key Terms**: The key terms in the question are "synthesis of urea" and "ammonia".

3. **Recalling Biological Processes**: Urea is produced from ammonia through a process known as the urea cycle (or ornithine cycle).

4. **Locating the Site of Urea Synthesis**: The urea cycle primarily occurs in the liver. This is where ammonia, which is toxic in high concentrations, is converted into urea, a less toxic compound that can be excreted from the body.

5. **Conclusion**: Therefore, the synthesis of urea from ammonia takes place in the liver.

### Final Answer:
The synthesis of urea from ammonia takes place in the **liver**.

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