How does the incipient phase affect the oxygen supply in the room?

During the incipient phase of a fire, the combustion process has just begun, and the fire is relatively small and contained. At this stage, the amount of oxygen consumed by the fire is minimal compared to the overall volume of oxygen present in the room. Since the fire is not yet large enough to significantly deplete the oxygen supply, the environment remains primarily safe in terms of breathable air.

As the fire continues to grow and progress to later phases, it will consume more oxygen, potentially leading to hazardous conditions. However, in the incipient phase, the oxygen depletion is not substantial enough to alter the overall air quality drastically, which is why this option accurately reflects the state of the room's oxygen supply.