The correct answer is A. AIS can be used to make passing arrangements via ship-to-ship text messaging, but a vessel operator is not relieved from the requirement to sound whistle signals or make arrangements via bridge-to-bridge radiotelephone. AIS provides additional means of communication, but does not replace the standard navigational rules and signals required for safe passing arrangements between vessels. The other options are incorrect because B is false - AIS does have the capability for ship-to-ship text messaging, C is false - AIS text messaging does not relieve the operator from making standard navigational signals, and D is false - the ship-to-ship text messaging feature is not limited to emergency use only.