Respuesta :
I would think it is the last answer because if what he said made Negi not have to work, it would mean that what he said made a difference, which would mean he had power over his family, making him the leader.
It's hard to picture how Negi's father is mean by making her not to work. There's no mention of Negi's sisters in a way that makes you believe that they're her father's favorites. Since the father has the final word, her mother most likely is not the leader of the family, but her father is, since he is the one who intervened.
The correct answer is: Negi's father is the leader of the family.