Answer:
His response does not seem rational to us because we are used to our freedoms but for Sergei he group up with the KGB just barging into his home at anytime. Now where Sergei lives he has privacy and he doesn't want anyone to bother his privacy.
Explanation:
Hope it helps
The second option is correct.
The melancholy in the tone emphasizes the effects of the grief and the grieving described in the excerpt.
They all look good to me. All of your answers is what I would have chosen. :)