Assertion:- Spore is the exclusive structure of slime moulds upon which cell wall remain present.
Reason:- Slime moulds differentiate and form fruiting body during unfavourable conditions in which spores remain filled.

Options

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

Answer

To analyze the given assertion and reason regarding slime molds, we will break down the statements step by step.

### Step 1: Understand the Assertion
The assertion states: "Spore is the exclusive structure of slime moulds upon which cell wall remain present."
- **Explanation**: In slime molds, spores are indeed a significant structure. They are produced during the life cycle of slime molds, particularly during unfavorable conditions. The assertion mentions that the cell wall remains present on these spores, which is true as spores are often encased in a protective cell wall made of cellulose.

### Step 2: Understand the Reason
The reason states: "Slime moulds differentiate and form fruiting body during unfavourable conditions in which spores remain filled."
- **Explanation**: This statement is also true. Slime molds undergo differentiation to form fruiting bodies when conditions are not favorable for growth. These fruiting bodies produce spores, which are filled with nutrients to help them survive until conditions improve.

### Step 3: Evaluate the Relationship
Now we need to evaluate whether the reason correctly explains the assertion.
- The assertion is about the structure of spores in slime molds, while the reason explains the process that leads to the formation of spores. The reason provides context for why spores are important and how they are formed, thus supporting the assertion.

### Conclusion
Both the assertion and the reason are true, and the reason provides a correct explanation for the assertion. Therefore, the correct answer is that both the assertion and reason are true, and the reason is the correct explanation of the assertion.

### Final Answer
The correct option is: **Both assertion and reason are true, and reason is the correct explanation of assertion.**

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