Assertion (A): A mineral is called ore, when metal is extracted from it conveniently and economically.
Reason (R): All ores are minerals but all minerals are not ores.

Options

A. Both A and R are true and R is the correct explanation of A.
B. Both A and R are true but R is NOT the correct explanation of A
C. A is true but R is false
D. A is false and R is true.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion (A)**:
- The assertion states that a mineral is termed an ore when it can be extracted for metal conveniently and economically.
- This means that not every mineral qualifies as an ore; only those from which metals can be extracted with relative ease and at a reasonable cost are classified as ores.

2. **Understanding the Reason (R)**:
- The reason states that all ores are minerals, but not all minerals are ores.
- This indicates that while every ore is indeed a mineral (since ores are derived from minerals), there are many minerals that do not qualify as ores because they cannot be extracted profitably or easily.

3. **Analyzing the Relationship**:
- The assertion is true because it correctly defines the criteria for a mineral to be classified as an ore.
- The reason is also true as it accurately describes the relationship between ores and minerals.

4. **Conclusion**:
- Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the statement is valid.

**Final Answer**: Both Assertion (A) and Reason (R) are true, and R explains A.

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