Explanation: For RADAR operation, the pulse width (PW) and pulse repetition rate (PRR) are critical parameters. 1. **Pulse Width (PW):** This determines the amount of energy in each transmitted pulse and influences range resolution. A longer pulse, such as 1.0 µs, carries more energy, which is essential for detecting targets at greater distances like 25 miles by improving the signal-to-noise ratio. Extremely short pulses (e.g., 0.01 µs or 0.05 µs) offer very high range resolution but would likely lack the energy to reliably detect a target at 25 miles. 2. **Pulse Repetition Rate (PRR):** This dictates the maximum unambiguous range of the radar. To avoid range ambiguity (where an echo from a previous pulse is mistaken for an echo from the current pulse), the round-trip time for the target must be less than the pulse repetition period (1/PRR). For a target at 25 miles, the round-trip time for the radar signal is approximately 269 µs. A PRR of 500 pps (pulses per second) corresponds to a pulse repetition period of 2000 µs (1/500), providing a maximum unambiguous range of 186 miles. This comfortably accommodates the 25-mile target. Combining these, a 1.0 µs pulse width ensures sufficient energy for detection at 25 miles, and a 500 pps PRR provides an appropriate unambiguous range. Options with very short pulse widths (C and D) would struggle to detect a target at this distance due to insufficient energy. While Option B offers better resolution, Option A prioritizes signal strength for detection at the specified range.