Slime moulds are mainly saprophytic.
Saprophytes get their nutrition from a host.

Options

A. If both As and R are correct and R is correct explanation of As
B. If both As and R are correct but R is not correct explanation of As
C. If As is correct, R is wrong
D. If both As and R are wrong.

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that "slime molds are mainly saprophytic." We need to evaluate if this statement is true or false.

- **Evaluation**: Slime molds are indeed classified as saprophytes because they obtain their nutrition from decomposing organic matter. This makes the assertion true.

2. **Understanding the Reason**: The reason provided is "saprophytes get their nutrition from a host." We need to determine if this statement is accurate.

- **Evaluation**: This statement is incorrect. Saprophytes do not derive their nutrition from a host; instead, they obtain nutrients from dead or decaying organic matter. Organisms that get their nutrition from a host are known as parasites.

3. **Conclusion**: Since the assertion is true and the reason is false, we can conclude that the correct relationship between the two statements is that the assertion is correct, but the reason is not.

4. **Final Answer**: The assertion is true, and the reason is false.

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