Statement I: Nitrogen and Oxygen are the main components in the atmosphere but these do not react to form oxides of nitrogen.
Statement: II: The reaction between nitrogen and oxygen requires high temperature.
Both assertion and reason are correct, and the reason is the correct explanation for the assertion.
Statement I istrue beause it is an observation that nitrogen being highly stable does not react with oxygen in atmosphere. The reaction to form oxides of nitrogen takes place at higher temperature (a2000 K as per NCERT). So, Statement II is correct and also the correct explanation of Statement I.