which of the following human system includes oesophagus ?

Options

A. respiratory system
B. circulatory system
C. digestive system
D. reproduction

Answer

**Step-by-Step Solution:**

1. **Identify the Options**: The question provides four options: Respiratory system, Circulatory system, Digestive system, and Reproductive system.

2. **Analyze the Respiratory System**: The respiratory system is responsible for breathing and gaseous exchange. Key organs include the lungs, diaphragm, and nose. The esophagus is not part of this system.

3. **Analyze the Circulatory System**: The circulatory system is involved in the circulation of blood and nutrients throughout the body. Key components include the heart, blood vessels, and capillaries. The esophagus is not included in this system either.

4. **Analyze the Digestive System**: The digestive system is responsible for breaking down food to extract energy. It starts from the mouth and ends at the anus. The esophagus is a crucial part of this system, as it is the tube that connects the throat to the stomach.

5. **Analyze the Reproductive System**: The reproductive system is involved in reproduction and includes organs such as ovaries in females and testicles in males. The esophagus does not belong to this system.

6. **Conclusion**: Based on the analysis, the esophagus is part of the digestive system. Therefore, the correct answer is the digestive system.

**Final Answer**: The esophagus is included in the **Digestive System**.

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