Assertion: Trypsinogen is activated by enterokinase into active trypsin which in turn activates other enzymes in the pancreatic juice
Reason: The pancreatic juice contains inactive enzymes which are activated by intestinal juice.

Options

A. If both assertion and reason are true and reason is the correct explantion of assertion
B. If both assertion and reason are true but reason is not the correct explnantion of assertion.
C. If assertion is true but reason is false.
D. If both assertion and reason are false.

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**: The assertion states that trypsinogen is activated by enterokinase into active trypsin, which then activates other enzymes in the pancreatic juice.
- **Explanation**: Trypsinogen is indeed an inactive precursor (zymogen) of the enzyme trypsin. It is converted into trypsin by the enzyme enterokinase, which is secreted by the intestinal mucosa. Once trypsin is formed, it can activate other zymogens present in the pancreatic juice, such as chymotrypsinogen and procarboxypeptidases.

2. **Understanding the Reason**: The reason states that pancreatic juice contains inactive enzymes which are activated by intestinal juice.
- **Explanation**: This statement is also correct. Pancreatic juice does contain several inactive enzymes (zymogens) that are activated in the small intestine. Enterokinase, which is part of the intestinal juice, activates trypsinogen to trypsin, and subsequently, trypsin activates other zymogens.

3. **Evaluating the Relationship**: Now we need to determine if the reason correctly explains the assertion.
- **Analysis**: While both statements are true, the reason provided does not specifically explain why trypsinogen is activated by enterokinase. The assertion focuses on the activation of trypsinogen, while the reason discusses the general presence of inactive enzymes in pancreatic juice.

4. **Conclusion**: Since both the assertion and reason are true, but the reason does not serve as the correct explanation for the assertion, the correct answer is option B: "Both assertion and reason are true, but reason is not the correct explanation of assertion."