Two glass jars a ana b are filled with carbondioxide and oxygen respectively. in each jar a lightened candle is placed simultaneously. in which jar the candle remain lightened?

Well the question doesn't make sense. because if you mean filled The jar right do the jars have lids. and if they do well have lids then the candle won't remain lightened in either. the candle in the carbon dioxide will go out first. and the other one will remain but it will go out after a few seconds because the carbon coming out of the candle flame will be consuming the oxygen and for a flame to keep on going one of the elements needed is oxygen.