If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
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The Correct Option isD
Solution and Explanation
In a group from left to right atomic number or nuclear charge or effective nuclear charge increase and size decrease, as a result ionisation energy increase. But elements of IIA and $VA$ group on the account of their half filled and completely filled orbitals respectively have stable configuration and so to remove electron from them comparatively larger energy has to be supplied.
$IA < IIA > III A < IVA < VA > VIA < VIIA$
The ionisation energy of $N ( VA )$ is more than $O$ (VIA)
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