(A) : Range is the largest distance between a source and a destination upto which the signal is received with sufficient strength
(R) : Use of repeater station to increase the range of communication

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 abd 'R' false
D. A' is false and 'R' is false

Answer

### Step-by-Step Solution

1. **Understanding the Assertion (A)**:
- The assertion states that "Range is the largest distance between a source and a destination up to which the signal is received with sufficient strength."
- This means that range refers to the maximum distance over which a communication signal can travel while still being strong enough to be effectively received.

2. **Evaluating the Assertion**:
- The assertion is correct because it accurately defines the concept of range in communication systems. The range is indeed determined by the strength of the signal and the distance it can cover.

3. **Understanding the Reason (R)**:
- The reason states that "Use of repeater station to increase the range of communication."
- A repeater station is a device that receives a weak signal and retransmits it at a higher power, allowing the signal to travel further distances.

4. **Evaluating the Reason**:
- The reason is also correct. Repeaters are commonly used in communication systems to extend the range by overcoming obstacles (like mountains) or to cover larger distances where the signal would otherwise weaken.

5. **Conclusion**:
- Both the assertion (A) and the reason (R) are true. Furthermore, the reason (R) provides a correct explanation for the assertion (A) because the use of repeaters directly contributes to increasing the effective range of communication.

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

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