The "law of nature" that Wollstonecraft accepts is that B. males are physically stronger that females.
Wollstonecraft was a zealous feminist, which means that she was advocating for women's rights bravely, especially for the time period she lived in (18th century). Given that she was one of the first feminists, it is obvious she wouldn't accept male supremacy when it comes to decisions about money, male logic/female emotion, and the last option. She believed that men and women are equal in those rights, but not when it comes to physical strength, which is obvious.