Whilst this is not technically on the learning objectives, this question is very easy to answer.

ADS-B (Automatic Dependent Surveillance - Broadcast) is a system which broadcasts an aircraft's position, identification and other useful pieces of information to ATC and other aircraft. It builds upon the technology of Secondary Surveillance Radar, but does not require an interrogation signal to transmit this data. This means that a short "delay" to the signal is no problem, as the timing of signals does not change the range the same way as a radar signal does (ADS-B uses GNSS derived position information, not RADAR pulse timing).

Therefore, the only other option that creates an erroneous (incorrect) ADS-B signal is an incorrectly transmitted or received signal.