Assertion : Pencillin has a narrow spectrum.
Reason : Antibiotics inhibit the growth or destroy micro-organisms.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "Penicillin has a narrow spectrum." This means that penicillin is effective against a limited range of bacteria, specifically targeting certain types of bacteria rather than all.

2. **Understanding the Reason**: The reason provided is that "Antibiotics inhibit the growth or destroy micro-organisms." This is a general statement about antibiotics, indicating that they work by either stopping the growth of bacteria or killing them.

3. **Classification of Antibiotics**: Antibiotics can be classified into two categories: narrow-spectrum and broad-spectrum. Narrow-spectrum antibiotics are effective against specific types of bacteria, while broad-spectrum antibiotics can act against a wider variety of bacteria.

4. **Penicillin's Classification**: Penicillin is classified as a narrow-spectrum antibiotic because it primarily targets Gram-positive bacteria and is not effective against a wide range of bacterial types. It is particularly used to treat infections like pneumonia caused by specific bacteria.

5. **Evaluating the Justification**: While the reason states a true fact about antibiotics in general, it does not specifically justify why penicillin is considered a narrow-spectrum antibiotic. The reason is correct in its own context but does not explain the assertion adequately.

6. **Conclusion**: Both the assertion and the reason are true statements. However, the reason does not serve as a correct justification for the assertion. Therefore, the answer to the question is that the assertion is true, the reason is true, but the reason is not the correct justification for the assertion.

**Final Answer**: Assertion is true, Reason is true, but Reason is not the correct justification for Assertion.

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