Assertion (A) : Gold threads are used in silk sarees.
Reason (R) : Gold is highly ductile by nature.

Options

A. Both (A) and (R) are true and (R) is the correct reason 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 but (R) is true.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Assertion (A)**: The assertion states that "Gold threads are used in silk sarees." We need to determine if this statement is true or false.
- **Evaluation**: Gold threads have indeed been used in silk sarees, particularly in traditional designs. While this practice has diminished due to the high cost of gold, it is still true that gold threads are used in silk sarees.
- **Conclusion**: The assertion is **true**.

2. **Understanding the Reason (R)**: The reason states that "Gold is highly ductile by nature." We need to evaluate if this statement is true and whether it explains the assertion.
- **Evaluation**: Ductility refers to the ability of a material to be stretched into a wire. Gold is known for its high ductility, which allows it to be drawn into very thin wires without breaking.
- **Conclusion**: The reason is also **true**.

3. **Connecting Assertion and Reason**: Now we need to determine if the reason explains the assertion.
- **Evaluation**: Since gold can be drawn into thin wires due to its ductility, it can be made into threads that can be used in silk sarees. Thus, the reason explains why gold threads are used in silk sarees.
- **Conclusion**: The reason does explain the assertion.

4. **Final Evaluation**: Both the assertion and reason are true, and the reason correctly explains the assertion.
- **Conclusion**: The correct answer is that both assertion and reason are true, and the reason is the correct explanation of the assertion.

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

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