Na is cation so it loses electron to be positive and become stable losing one valence shells one electron so it's oxidation number is +1 ie A is correct
An oxidising agent oxidises something else. Oxidation is loss of electrons (OIL RIG). That means that an oxidising agent takes electrons from that other substance.
About 19.64 pounds of carbon dioxide are produced from burning a gallon of gasoline. On the other hand, 22.38 pounds of carbon dioxide are produced from burning a gallon of diesel. So, different fossil fuels will give different amounts of carbon dioxide to be released.
