Dear Dr. J Chakma Sir
Thank you so much for your thoughtful answer. Yes, I agree with you on both of your points (a) and (b). I had also come to a similar conclusion.
Also, thanks a lot for your important advice. Yes you said it right.
We should not worry and waste our time on these questions. We should follow Lord Buddha’s Dhamma with our best possible efforts.
May you attain Nibbana in this life itself !