What components are disabled when the black-out service select switch is set to the on position?

Answer: B — Break lights and turn signals

When the black-out service select switch is set to the on position, the components that are disabled primarily include the brake lights and turn signals. This functionality is crucial for military operations during nighttime or in low-visibility situations where maintaining stealth is necessary. Disabling these components helps reduce visibility from afar and prevents the vehicle from being easily detected by the enemy. In this scenario, turning off the brake lights and turn signals means that the vehicle can still operate without drawing attention to itself, addressing safety concerns while still adhering to operational security protocols. This understanding of the vehicle's operational capabilities during tactical driving situations underlines the importance of using the black-out service select switch correctly to maintain stealth. Other components such as headlights may still operate under a different configuration to provide necessary navigation without revealing the vehicle's location as much, which is why an understanding of what exactly the black-out switch controls is vital for military personnel operating such vehicles.