Question

why is carbon dioxide considered the best fire extinguisher

Answer 1

the carbon dioxide is also very cold as it comes out of the extinguisher, so it cools the fuel as well. CO2s may be ineffective at extinguishing Class A fires because they may not be able to displace enough oxygen to successfully put the fire out. Class A materials may also smolder and re-ignite.

Answer 2

because fire needs oxygen burn but when carbon dioxide is there the supply of oxygenbis cut therefore it leads to extinguish the fire