The major site of protein breakdown to form free animo acids, is in the

Options

A. Kidney
B. Spleen
C. Liver
D. Bone marrow

Answer

### Step-by-Step Solution:

1. **Identify the Question**: The question asks for the major site of protein breakdown to form free amino acids in the human body.

2. **Understand Protein Metabolism**: Protein metabolism involves the breakdown of proteins into smaller units called amino acids. This process is essential for various bodily functions, including the synthesis of new proteins and energy production.

3. **Locate the Site of Protein Breakdown**: The liver is known to be the primary organ responsible for various metabolic processes, including the breakdown of proteins.

4. **Deamination Process**: In the liver, the process of deamination occurs, where the amino group (NH2) is removed from amino acids. This process is crucial for converting amino acids into usable forms for energy or storage.

5. **Conversion of Ammonia**: After deamination, the removed amino group is converted into ammonia, which is then transformed into urea. Urea is less toxic and is excreted from the body through urine.

6. **Final Conclusion**: Based on the understanding of protein metabolism and the role of the liver in this process, we conclude that the major site of protein breakdown to form free amino acids is the liver.

### Answer:
The major site of protein breakdown to form free amino acids is the **liver**.

---