Calf thymus is an important source of .

Options

A. Amylases
B. Renin
C. Vitamin
D. Protein

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the important source found in the calf thymus.

2. **Identifying the Key Component**: The calf thymus is known to produce specific substances. In this case, we need to identify what is predominantly sourced from the calf thymus.

3. **Recognizing the Substance**: The calf thymus is recognized as an important source of renin, which is a specific type of enzyme.

4. **Understanding Renin**: Renin is classified as a proteolytic enzyme, meaning it helps in breaking down proteins. It is similar to pepsin, another enzyme involved in digestion.

5. **Function of Renin**: The primary role of renin is to aid in the digestion of coagulated milk. This is particularly relevant in the context of young mammals, including calves, which consume milk.

6. **Conclusion**: Therefore, the calf thymus is an important source of renin, which is the correct answer.

**Final Answer**: Calf thymus is an important source of renin.

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