INLAND ONLY Two vessels in a crossing situation have reached agreement by radiotelephone as to the intentions of the other. In this situation, whistle signals are __________.

Correct Answer: Option D — not required, but may be sounded

Under Inland Rule 34(h), if agreement for passing is reached by VHF radiotelephone, whistle signals are not required, but if agreement is not reached, whistle signals must be exchanged.