2081. A tug should not come alongside a tank vessel in way of its cargo tanks while it is loading grade A, B, or C cargo without the permission of the __________.

A tug approaching a tank vessel's cargo tanks during Grade A, B, or C cargo loading requires permission from the person in charge of the transfer, as regulations mandate direct operational control for hazardous cargo transfers and prioritize the PIC's authority over shoreside personnel or external agencies.