B i think im not 100 % sure
It brings out a sences of trust and hurt.
From the excerpt given above, 'fits in' as used in this passage means to feel comfortable and acceptable in a place, thus the correct option is A. An idiom is a group of words that is not taken literally, that is, their meaning can not be deduced from those of individual word. 'Fit in' as an idiom means to be comfortable with something or someone, to be in harmony with that thing.
The people of Sighet, like many Jewish people in Europe at the time, are naive and unable to believe the atrocities being committed by the Nazis.
When Moshe returns to Sighet and tells everyone about what he experienced, they are unable to believe him. Instead of believing him, the people of Sighet say he is crazy. If they were to believe him, they would have to admit the fact they were in danger as well. They do not believe until it is far too late to leave.