Explanation: RADAR measures range by sending out a radio pulse and timing how long it takes for the echo to return. Radio waves travel at approximately the speed of light, which is $3 \times 10^8$ meters per second. This means in one microsecond ($10^{-6}$ seconds), a radio wave travels 300 meters. Since the RADAR measures the *total round trip* time (out to the target and back), the actual one-way distance to the target is half of the total distance traveled by the pulse. Therefore, for every microsecond of elapsed time, the target is 300 meters / 2 = 150 meters away. This is a fundamental constant used in RADAR calculations. Options B and C are incorrect because they use "yards" instead of "meters," and C represents the total round-trip distance, not the one-way range. Option D is an incorrect value and unit combination for this calculation.