Correct option (b) Both A and R are true but R is not correct explanation of A
Explanation:
Due to the absence of unpaired electron in NO+ and N2, both are diamagnetic in nature.
Total no. of e- in NO+= 7 + 8 - 1 = 14
Total no. of e- in N2 = 7 + 7 = 14
Therefore. both are isoelectronic.