There is one difference between the sexes on which every expert and study agrees: men are more aggressive than women. It shows up in 2-year-olds. It continues through school days and persists into adulthood. It is even constant across cultures. And there is little doubt that it is rooted in biology. If there's a woman's trait  which is the same as men's aggressiveness, it's what social scientists refer to as the result of "education". Feminists have argued that the caring nature of women is not biological in origin, but rather has been forced into women by a society that wanted to keep them in the home. But the signs that it is at least partly inborn are too numerous to ignore. Just as tiny infant girls respond more readily to human faces, female toddlers  learn much faster than males how to pick up nonverbal cues  from others. And grown women are far more skilful than men at interpreting facial expressions: A recent study by University of Pennsylvania brain researcher Ruben Gur showed that they easily read emotions such as anger, sadness and fear. The only such emotion men could pick up was disgust. What difference do such differences make in the real world? Among other things, women appear to be somewhat less competitive--or at least competitive in different ways--than men. At the Harvard Law School, for instance, female students enter with qualities just as outstanding as those of their male peers. But they don' t qualify for the well-known Law Review in proper numbers, a fact some school officials owe to women' s discomfort in the incredibly competitive atmosphere. Students of management styles have found fewer differences than they expected between men and women who reach leadership positions, perhaps because many successful women deliberately imitate men. But an analysis by Purdue social psychologist Alice Eagly of 166 studies of leadership style did find one difference: Men tend to be more "autocratic"-making decisions on their own--while women tend to consult colleagues more often.  Studies of behavior in small groups turn up even more differences. Men will typically dominate the discussion, says University of Toronto psychologist Kenneth Dion, spending more time talking and less time listening. Which of the following is true of women's nurturing nature according to the passage?
It is not inborn in any sense. It is inspired by women's families. It is caused by social prejudice. It is partly biological in origin.