B. Amygdala. The amygdala is responsible for your knee-jerk response to a stimulus, like an actor jumping out at you in a haunted house. Your hippocampus and prefrontal cortex then interpret context, telling you that you’re not actually in danger.
C. Well...it’s complicated. It’s not that fear isn’t real, it’s just that scientists can’t yet experimentally parse the emotional feeling of fear from its many physical manifestations, like anxiety, defensiveness, or aggression.