What is the operational benefit of the fuel tanks being pressurized?

The operational benefit of pressurizing the fuel tanks is primarily to prevent vapor lock. Vapor lock occurs when the fuel vaporizes in the fuel system due to low pressure, which can obstruct fuel flow to the engines, potentially leading to engine performance issues or engine failure. By maintaining pressure in the fuel tanks, the system ensures that the fuel remains in a liquid state, even at lower temperatures or altitudes, thus preventing vaporization and ensuring reliable fuel delivery to the engines.

The other options relate to fuel management but do not address the specific functionality of pressurization. Enhancing fuel efficiency and increasing fuel flow rate refer to performance aspects that can be influenced by various factors but are not directly linked to the mechanics of pressurization. Maintaining structural integrity is more about the physical robustness of the tanks rather than their operational function. Therefore, preventing vapor lock is the most relevant and critical benefit of pressurized fuel tanks in aircraft like the Dassault Falcon 7X.