(A) : Communication in UHF/VHF regions can be established by space wave or tropospheric wave
(R) : Communication in UHF/VHF regions is limited to line of sight distance

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

To analyze the given statements, we will evaluate both the assertion (A) and the reason (R) step by step.

### Step 1: Understanding the Assertion (A)
The assertion states: "Communication in UHF/VHF regions can be established by space wave or tropospheric wave."

- **Explanation**: UHF (Ultra High Frequency) and VHF (Very High Frequency) are frequency ranges used for various communication systems. Space wave propagation is a method used in these frequency ranges where the waves travel directly from the transmitter to the receiver, typically in a line-of-sight manner. Tropospheric waves are a type of space wave that can bend slightly due to atmospheric conditions, allowing communication over slightly longer distances.

### Step 2: Understanding the Reason (R)
The reason states: "Communication in UHF/VHF regions is limited to line of sight distance."

- **Explanation**: This statement is also true. In UHF and VHF communication, the waves do not reflect off the ionosphere, which means that they cannot travel beyond the line of sight. This limitation is due to the nature of the propagation of these waves, which necessitates a direct path between the transmitter and receiver.

### Step 3: Evaluating the Relationship between A and R
Now we need to determine if the reason (R) correctly explains the assertion (A).

- **Analysis**: While both statements are true, the reason does not provide a justification for the assertion. The assertion discusses the methods of communication (space waves and tropospheric waves) while the reason discusses the limitation of communication distance (line of sight). The reason does not explain why space wave or tropospheric wave communication is possible; it merely states a limitation.

### Conclusion
- **Final Evaluation**:
- Assertion (A) is true.
- Reason (R) is true.
- However, R does not correctly explain A.

Thus, the correct answer is that both A and R are true, but R is not the correct explanation of A.

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