The most accurate answer is:
Her familiarity allows her to invent an otherworldly explanation for events she can easily predict; Nuttel's unfamiliarity makes him believe this as truth.
This choice highlights how Vera, being familiar with her surroundings and the family dynamics, is able to fabricate a story that plays on Nuttel's ignorance of the situation. His unfamiliarity with the setting leads him to accept her story as genuine, creating the central twist in the narrative.