The Gas Phase Reaction of Nitrogen Dioxide and Carbon Monoxide $\rarr$

The gas phase reaction of nitrogen dioxide and carbon monoxide was found experimentally to be second-order with respect to NO₂, and zero-order with respect to CO below 25°C. NO₂ + CO $\rarr$ NO + CO₂
Which one of the following mechanisms is consistent with the observed reaction order?

A) NO₂ + 2CO N + 2CO₂ fast N + NO₂ $\rarr$ 2NO slow
B) NO₂ + 2CO $\rarr$ N + 2CO₂ slow N + NO₂ $\rarr$ 2NO fast
C) NO₂ + NO₂ $\rarr$ NO₃ + NO fast NO₃ + CO $\rarr$ NO₂ + CO₂ slow
D) NO₂ + NO₂ $\rarr$ NO₃ + NO slow NO₃ + CO $\rarr$ NO₂ + CO₂ fast