I think it would be simple since it only has one subject (it) and one predicate (is).
Answer could be any of the above EXCEPT for B at her synagogue.
Anti-semitism means anti-jewish essentially. Synagogue is where she would go to worship and thus be the one place where she wouldn't encounter it.
If it's an "early" experience being the distinction then the most likely answerw would be C. in her school
It’s A people can stop the coming climate disaster, but they must act now.
