(A): A tuning fork is made of an alloy of steel, nickel and chromium.
(R): The alloy of steel, nickel and chromium is called Elinvar

Options

A. Both 'A' and 'R' are true and 'R' is the correct, explanation of 'A'.
B. Both 'A' and 'R' are true and 'R' is not the correct explanation of 'A'
C. A' is true and 'R' is false
D. Both 'A' and 'R' are false

Answer

To solve the assertion-reason question, we will analyze both the assertion and the reason statements step by step.

### Step 1: Analyze the Assertion
The assertion states: "A tuning fork is made of an alloy of steel, nickel, and chromium."
- **True or False?**: This statement is true. Tuning forks are indeed made from alloys that typically include steel, nickel, and chromium, as these materials provide the necessary properties for sound production.

### Step 2: Analyze the Reason
The reason states: "The alloy of steel, nickel, and chromium is called Elinvar."
- **True or False?**: This statement is also true. Elinvar is a specific alloy that includes nickel and chromium, and it is known for its constant elasticity, which is essential for the functionality of tuning forks.

### Step 3: Determine the Relationship
Now we need to determine if the reason is the correct explanation of the assertion.
- The assertion is about the composition of the tuning fork, while the reason explains a specific property of the alloy (constant elasticity) that makes it suitable for tuning forks.
- Although both statements are true, the reason does not directly explain why the tuning fork is made of that specific alloy. Instead, it explains a property of the alloy.

### Conclusion
Based on the analysis:
- Both the assertion and reason are true.
- However, the reason is not the correct explanation of the assertion.

Therefore, the correct answer is: **Option 2: Both assertion and reason are true, but reason is not the correct explanation of assertion.**

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