What is the general effect of reduced oxygen levels on combustion?

Reduced oxygen levels have a significant effect on combustion, primarily leading to flame extinguishment. For combustion to occur, a sufficient amount of oxygen is required to react with the fuel. When oxygen levels drop, the available reactant for the chemical reaction that produces fire diminishes. This insufficient oxygen can lead to incomplete combustion, which results in a reduced intensity of the flame or complete extinguishment if the oxygen concentration falls below the threshold required for combustion to sustain itself.

In scenarios with low oxygen, flames may flicker, burn more slowly, or even go out completely, as the combustion process cannot occur efficiently. This makes it clear that a lack of oxygen directly contributes to the inability of a flame to maintain itself, ultimately leading to extinguishment. Thus, the correct understanding of the relationship between reduced oxygen levels and combustion aligns with the conclusion that flame extinguishment is the general consequence.