Assertion :- Diffusion is a passive transport.
Reason:-Diffusion occurs against concentration gradient

Options

A. If both Assertion & Reason are True & the Reason is a correct explanation of the Assertion.
B. If both Assertion & Reason are True but Reason is not a correct explanation of the Assertion.
C. If Assertion is True but the Reason is False
D. If both Assertion & Reason are false.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step-by-Step Solution:

1. **Understanding the Assertion**:
- The assertion states that "Diffusion is a passive transport."
- This statement is **true** because diffusion is a process where molecules move from an area of higher concentration to an area of lower concentration without the need for energy input.

2. **Understanding the Reason**:
- The reason states that "Diffusion occurs against the concentration gradient."
- This statement is **false** because diffusion, by definition, occurs along the concentration gradient (from high to low concentration). When substances move against the concentration gradient, it requires energy and is classified as active transport.

3. **Evaluating the Relationship**:
- Since the assertion is true and the reason is false, the reason does not correctly explain the assertion.

4. **Conclusion**:
- The correct answer is that the assertion is true, but the reason is false.

### Final Answer:
- The correct option is: **Assertion is true, but Reason is false.**

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