Doubt from aromatic compounds

Answer is given as B. I am getting D. Can anyone help?

Is my answer correct ?

Yes but plz elaborate why you chose D as correct one and not B for everybody who will read this thread of yours @deep_2020

Sure, the lone pairs of nitrogen to which the methyl group is attached in option B are de localised due to aromaticity so effective electron density available to kick out Iodine is far less than in option D where the nitrogen to which methyl is attached is non delocalised as it doesn't take part in resonance.

P.S anyone using Arihant's archives, be aware that some of the solutions in Arihant Chemistry archive are wrong