Question 4361 Deck General

The correct answer is D) 48 Port. When deballasting using tanks 1P and 10P of the DEEP DRILLER, the valve that needs to be opened is the 48 Port valve. This is because the 48 Port valve is the valve that controls the flow of water from the 1P and 10P ballast tanks during the deballasting process. The other answer choices (A, B, and C) are incorrect because they do not correspond to the specific valve that needs to be opened for deballasting the 1P and 10P tanks on the DEEP DRILLER. The valves referenced in these choices likely serve different functions or are associated with different components of the vessel's ballast system.