What does "Remaining on board" indicate?

"Remaining on board" refers specifically to the amount of fuel or cargo that is still present in a vessel’s tanks after a discharge operation has been completed. In the context of tanks that have been emptied of their contents for the purpose of either fuel transfer or cargo handling, this term highlights the critical operational data that tankerman assistants and other crew members need to keep track of, ensuring that safety and compliance regulations are adhered to. This is essential for calculating tank capacities accurately, managing operational risks, and planning future loading or discharge activities.

While the other options refer to various states of fuel or cargo quantities, only the concept of "remaining on board" directly correlates with the specific amount of fuel that remains in the tanks after unloading, making it the most accurate choice in this context.