The site of complete digestion and adsorption of food in the human digestive system is :

Options

A. stomach
B. small intestine
C. large intestine
D. rectum

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for the site of complete digestion and absorption of food in the human digestive system.

2. **Identify the Options**: The options provided are:
- Stomach
- Small intestine
- Large intestine
- Rectum

3. **Analyze Each Option**:
- **Stomach**: The stomach is involved in the digestion of food, primarily breaking down proteins with the help of enzymes like pepsin and hydrochloric acid. However, it does not complete the digestion or absorption of all nutrients.
- **Small Intestine**: The small intestine is where the majority of digestion and absorption occurs. It is divided into three parts: duodenum, jejunum, and ileum. Here, complex food substances are broken down into simpler forms (like glucose, fatty acids, and amino acids) and absorbed into the bloodstream.
- **Large Intestine**: The large intestine primarily absorbs water and some minerals from undigested food. It does not play a significant role in the digestion of food.
- **Rectum**: The rectum is the final part of the large intestine and is responsible for storing waste before it is excreted. It does not participate in digestion or absorption.

4. **Conclusion**: Based on the analysis, the small intestine is the site of complete digestion and absorption of food in the human digestive system.

5. **Final Answer**: The site of complete digestion and absorption of food in the human digestive system is the **small intestine**.

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