A:Oxygen is the most abundant element on the surface of earth.
R: Aluminium is the most abundant metal in Earths crust.

Options

A. If both (A) and ( R) are correct and ( R) is the correct explanation of (A).
B. If both (A) and ( R) are correct, but ( R) is not the correct explanation of (A).
C. If (A) is correct, but ( R) is incorrect.
D. If (A) is incorrect, but ( R) is correct.

Answer

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

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**:
- The assertion states that "Oxygen is the most abundant element on the surface of the Earth."
- This is true. Oxygen constitutes about 21% of the Earth's atmosphere by volume and is also a major component of water (H2O) and various minerals in the Earth's crust.

2. **Understanding the Reason (R)**:
- The reason states that "Aluminium is the most abundant metal in Earth's crust."
- This statement is also true. Aluminium makes up about 8.1% of the Earth's crust, making it the most abundant metal.

3. **Evaluating the Relationship**:
- While both the assertion and the reason are true, we need to determine if the reason explains the assertion.
- The assertion talks about oxygen as the most abundant element, while the reason discusses aluminium as the most abundant metal. These are two different categories (element vs. metal) and do not directly explain one another.

4. **Conclusion**:
- Both the assertion and the reason are correct statements, but the reason does not provide an explanation for the assertion. Therefore, we conclude that:
- Assertion (A) is true.
- Reason (R) is true.
- However, R is not the explanation for A.

### Final Answer:
Both assertion and reason are correct, but the reason does not explain the assertion.

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