To solve the question, we will analyze both the assertion (A) and the reason (R) given in the statement.
### Step 1: Analyze the Assertion (A)
- The assertion states that "Cu, Ag, Au are known as coinage metals."
- Coinage metals are traditionally defined as metals that have been historically used to make coins.
- Copper (Cu), Silver (Ag), and Gold (Au) have been used for this purpose for centuries, thus confirming that the assertion is true.
### Step 2: Analyze the Reason (R)
- The reason states that "Coinage metals are d-block metals."
- The d-block of the periodic table consists of transition metals, which include elements like Copper (Cu), Silver (Ag), and Gold (Au).
- Copper is a 3d element, Silver is a 4d element, and Gold is a 5d element, all of which belong to the d-block of the periodic table.
- Therefore, this reason is also true.
### Step 3: Determine the Relationship Between A and R
- While both the assertion and the reason are true, we need to assess whether the reason correctly explains the assertion.
- The reason states that coinage metals are d-block metals, but not all d-block metals are used for making coins. There are many d-block metals that do not qualify as coinage metals.
- Thus, while the reason is true, it does not serve as a correct explanation for the assertion.
### Conclusion
- Both the assertion (A) and the reason (R) are true, but the reason is not the correct explanation for the assertion.
- Therefore, the correct answer to the question is that both statements are true, but the reason does not explain the assertion.
### Final Answer
- Both A and R are true, but R is not the correct explanation for A.
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