Catalytic converter

A catalytic converter is a vehicle emissions control device that converts toxic pollutants in exhaust gas to less toxic pollutants, by catalyzing a redox reaction (oxidation or reduction). Catalytic converters are used in internal combustion engines fueled by either petrol (gasoline) or diesel—including lean burn engines. Most of engines generate nitrogen oxide, and the catalytic converter decomposes them. The above shows a part of this reaction, where reaction (X) occurs in the engine and reaction (Y) occurs in the catalytic converter. Which of the following statements is correct about these reactions?

a) A is N $_2$ and B is $2$ CO $_2$ .

b) A is oxidized in reaction X.

c) CO acts as a reductant in reaction Y.