You receive an Urgency DSC call to all vessels specifying an alternate TELEX frequency & emission. If your transceiver frequency display reads: 2174.5 kHz transmit & 4207.5 kHz receive:

Correct Answer: Option C — Both a) and d) are true

A mismatch between the DSC controller's decoded frequency and the transceiver's display indicates either a formatting error by the transmitting station or a failure in the controller's ability to process the alternate frequency field. Operators must verify both the received data log and the transceiver settings to ensure correct communication.