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 D — officer in charge of the vessel which is loading

Per 33 CFR 154.500, the person in charge of the vessel loading hazardous cargo must authorize any vessel coming alongside. This ensures the safety of the transfer operation and prevents unauthorized proximity to dangerous cargo, maintaining strict control over the vessel's immediate environment during critical loading procedures.