Which of the given gases present in the atmospheric air does support burning of a lighted candle?

For combustion to occur (that is a fire to start), oxygen must be present. Fire is a chemical reaction that creates light and heat from oxygen and fuel. A lit candle needs to draw oxygen from the air in order to continue burning. If you limit the amount of air available, the candle's flame eventually goes out once it uses up all the oxygen. When a candle burns, the wax is reacting with oxygen in the air to give out heat and light. If you give the candle more oxygen, then it will burn brighter but it will burn out more quickly. It all depends whether the candle has a high or low concentration of oxygen.