Assertion: Insulin used in diabetes was earlier extracted from pancreas of slaughtered cattle and pigs
Reason: Insulin from an animal source caused some patients to develop allergy or other types of reactions to the foreign protein

Options

A. develop allergy
B. decreased immunity
C. Cancer
D. lower metabolism

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that insulin used for treating diabetes was historically extracted from the pancreases of slaughtered cattle and pigs. This is true as, before the advent of recombinant DNA technology, animal insulin was the primary source for diabetic patients.

2. **Understanding the Reason**:
- The reason given is that insulin derived from animal sources can cause some patients to develop allergies or other types of reactions to the foreign protein. This is also true, as animal insulin can be recognized as a foreign substance by the human immune system, leading to allergic reactions in some individuals.

3. **Evaluating the Relationship**:
- While both the assertion and the reason are correct, we need to analyze whether the reason adequately explains the assertion. The assertion is about the historical source of insulin, while the reason discusses the potential allergic reactions caused by animal-derived insulin.

4. **Conclusion**:
- Since both the assertion and the reason are correct, but the reason does not explain why insulin was extracted from animals (it does not relate to the necessity or historical context), we conclude that:
- The assertion is correct.
- The reason is correct.
- However, the reason does not explain the assertion.

### Final Answer:
- The assertion is correct, the reason is correct, but the reason does not explain the assertion.

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