Assertion (A): Vice is used to hold metal plates or rods.
Reason (R): It is difficult to hold metal rods which have to be cut in one's hand.

Options

A. Both A and R are correct and R is the correct explanation of A.
B. Both A and R are correct but R is not the correct explanation of A.
C. A is correct and R is incorrect.
D. Both A and R are incorrect.

Explanation

### Step-by-Step Solution:

1. **Understanding the Assertion (A)**: The assertion states that "Vice is used to hold metal plates or rods."
- A vice is indeed a tool commonly found in workshops, designed specifically to hold objects securely in place. This allows for easier manipulation or cutting of the materials.

2. **Understanding the Reason (R)**: The reason states that "It is difficult to hold metal rods which have to be cut in one's hand."
- This statement is true as well. Holding a metal rod in one hand while trying to cut it with a saw in the other can be very challenging and unsafe. A vice provides a stable grip, allowing both hands to be free for cutting or other tasks.

3. **Evaluating the Relationship**: Now, we need to determine if the reason correctly explains the assertion.
- The assertion is true because a vice is indeed used to hold metal plates or rods. The reason is also true, as it highlights the difficulty of holding metal rods by hand while cutting. Therefore, the reason supports the assertion.

4. **Conclusion**: Since both the assertion and the reason are true, and the reason provides a correct explanation for the assertion, we conclude that:
- Both A and R are correct, and R is the correct explanation of A.

### Final Answer:
Both A and R are correct, and R is the correct explanation of A.

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