According to Coast Guard Regulations (46 CFR), no vessel can come alongside or remain alongside a tank vessel while it is loading A, B, or C grade cargo without having the permission of the __________.

Correct Answer: Option C — officer in charge of the vessel which is loading

46 CFR 35.01-1 requires the officer in charge of a tank vessel loading hazardous Grade A, B, or C cargoes to authorize any vessel coming alongside. This control measure prevents unauthorized vessels from entering the hazardous zone, thereby mitigating the risk of fire or explosion during critical loading operations.