Why is it not legal to transmit a 3 kHz bandwidth USB signal with a carrier frequency of 14.348 MHz?

Question

Accepted Answer

The correct answer is D: The upper 1 kHz of the signal is outside the 20-meter band. Why it is not legal to transmit a 3 kHz bandwidth USB signal with a carrier frequency of 14.348 MHz is that the upper 1 kHz of the signal is outside the 20-meter band. 20-meter band ends at 14.350 MHz; 14.348 + 1.5 kHz (half bandwidth) = 14.3495 MHz is OK, but the upper sideband extends to 14.348 + 3 kHz = 14.351 MHz, which exceeds 14.350 MHz. For amateur radio operators, this is important for band compliance. Understanding this helps ensure legal operation.