How many lines of symmetry does the above figure have ?

Options

A. 2 and 5
B. 2 and 3
C. 3 and 4
D. 2 and 4

Answer

C

Explanation

If we draw all the resonating structures, we will see that all carbon atoms will have equal electron density.
But resonance is not the only phenomenon here. If we consider inductive effect then carbon close to nitrogen should have lesser electron density than carbon far away from nitrogen. Thus C-3 and C-4 should have more electron density than C-2 and C-5.