The answer to this question is B. Nv2O. The generic term for Nitrogen Oxide is actually NOx. This is known to be somewhat hazardous to the health because it can change into Nitrogen Dioxide which is known to cause acid rain and smog. There are different reasons why Nitrogen Oxide forms.
The pollution coming from cars is just one example. There is also pollution coming from various factories. There are some people who are trying their best to reduce the production of nitrogen oxide but this is not always easy because of all the things that people consider to be their “needs” in this world.
The oxidation number for Oxygen (O) is -2 and the oxidation number for Nitrogen (1) is +1. Since this is a compound, the oxidation numbers of the atoms in the compound must equal zero. In Nv2O, note how N (2)(+1) or a +2 charge will cancel out the -2 charge of one oxygen ion.