Which of the following is the largest lymphatic vessel of the human body ?

Options

A. (a) Lacteal duct
B. (b) Thoracic duct
C. (c) Cisterna chyle
D. (d) Right lymphatic duct

Answer

**Step-by-Step Solution:**

1. **Understanding Lymphatic System**: The lymphatic system is a crucial part of the circulatory system, responsible for maintaining fluid balance in the body, transporting fats, and playing a role in immune function.

2. **Identifying Functions of Lymph**: The primary functions of lymph include:
- Draining excess fluid from tissues back into the bloodstream.
- Transporting dietary fats from the digestive system.
- Producing and transporting immune cells.

3. **Determining the Largest Lymphatic Vessel**: Among the various lymphatic vessels in the human body, we need to identify the largest one.

4. **Recognizing the Thoracic Duct**: The thoracic duct is recognized as the largest lymphatic vessel. It is responsible for transporting approximately 75% of the lymph from the entire body back to the bloodstream.

5. **Conclusion**: Based on the information, the thoracic duct is the largest lymphatic vessel in the human body.

**Final Answer**: The largest lymphatic vessel of the human body is the **thoracic duct**.

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