A : Slime moulds form fruiting bodies under unfavourable conditions.
R : Naked plasmodium is formed during favourable conditions.

Options

A. If both assertion & reason are true and the reason is the correct explanation of the assertion
B. If both assertion & reason are true but the reason is not the correct explanation of the assertion
C. If assertion is true statement but reason is false
D. If both assertion and reason are false statements

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that slime molds form fruiting bodies under unfavorable conditions. This is a true statement. Slime molds, when faced with adverse environmental conditions, will produce fruiting bodies to ensure the survival of their species.

2. **Understanding the Reason**:
- The reason provided states that a naked plasmodium is formed during favorable conditions. This is also a true statement. Under favorable conditions, slime molds aggregate to form a multinucleated structure called plasmodium, which is referred to as "naked" because it lacks a cell wall.

3. **Analyzing the Relationship**:
- While both the assertion and reason are true, we need to determine if the reason correctly explains the assertion. The assertion talks about the formation of fruiting bodies in unfavorable conditions, while the reason describes the formation of plasmodium in favorable conditions. These are two distinct processes in the life cycle of slime molds.

4. **Conclusion**:
- Since both statements are true but the reason does not explain the assertion, we conclude that the correct answer is that both the assertion and reason are true, but the reason is not the correct explanation of the assertion.

### Final Answer:
Both assertion and reason are true, but reason is not the correct explanation of the assertion.

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