Opening of stomach into small intestine is guarded by

Options

A. Cardiac sphincter
B. Anterior oesophageal sphincter
C. Pyloric sphincter
D. Sphincter of Oddi

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which sphincter guards the opening of the stomach into the small intestine.

2. **Identifying the Relevant Sphincters**: The options provided are:
- Cardiac sphincter
- Anterior esophageal sphincter
- Pyloric sphincter
- Sphincter of Oddi

3. **Analyzing Each Option**:
- **Cardiac Sphincter**: This sphincter is located at the junction of the esophagus and the stomach. It does not guard the opening into the small intestine.
- **Anterior Esophageal Sphincter**: This sphincter is also located at the upper end of the esophagus and does not relate to the stomach's opening into the small intestine.
- **Pyloric Sphincter**: This sphincter is located at the lower end of the stomach, where it connects to the duodenum (the first part of the small intestine). This sphincter regulates the passage of food from the stomach into the small intestine.
- **Sphincter of Oddi**: This sphincter controls the flow of digestive juices (bile and pancreatic juice) from the liver and pancreas into the duodenum, but it does not guard the opening from the stomach to the small intestine.

4. **Conclusion**: The sphincter that guards the opening of the stomach into the small intestine is the **Pyloric Sphincter**.

5. **Final Answer**: Pyloric sphincter.

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