Explanation: For routine follow-on voice communications between two vessels, a dedicated working channel should be used. **Ch-08** is a designated VHF marine inter-ship working channel. After making initial contact (often on Ch-16 or via DSC on Ch-70), stations engaged in routine conversations are required to move to a working channel to conduct their traffic. Ch-08 is appropriate for commercial and general inter-ship communications. **Ch-70** is the Digital Selective Calling (DSC) channel, used exclusively for digital signaling, distress alerts, and initial calls; it is not for voice communications. **Ch-16** is the international distress, urgency, safety, and *calling* channel. For routine calls, once contact is established, vessels *must* switch to a working channel to keep Ch-16 clear for other calls or distress traffic. **Ch-22** (specifically Ch-22A in the US) is primarily for communications with the Coast Guard and safety-related broadcasts or liaison, not a general routine inter-ship working channel.