“Silence is a valid option” is something that shows up when we have the first chance to choose a dialog line. I particularly almost never choose that option. Someone, however, decided to just do that:
The videos cut the part where Lee has to speak (like when you can’t choose), but it is really funny to see the characters’ reactions to Lee’s silence. This also raises a question of how much your choices actually affect the game, although it does change the impressions of the other people towards you, like making them angry or confused.