Explanation: Automatic Identification System (AIS) units are mandated to operate on specific, internationally designated VHF marine channels to ensure interoperability and avoid interference with other critical marine communications. These dedicated channels are 87B (161.975 MHz) and 88B (162.025 MHz). AIS employs a digital communication scheme, utilizing GMSK (Gaussian Minimum Shift Keying) modulation for robust data transmission. The standard data rate for AIS is 9.6 kilobits per second (kbs), which is efficient for transmitting the periodic bursts of vessel navigation data. Option B accurately identifies these specific VHF channels, the correct data rate, and the modulation type, all of which are fundamental regulatory and technical specifications for AIS operation. Options A, C, and D are incorrect as they list either incorrect frequencies, different channels (like distress channel 16 or DSC channel 70), or an incorrect data rate for AIS.