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(特点) 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(学步者) learn much faster than males how to pick up nonverbal cues（非言语暗示） 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.
The passage mainly discusses__________.
　          

A．how sex differences are demonstrated in social relations

B．how hormone determines sex differences

C．why there are differences between males and females

D．why men and women have different social roles

Which of the following is true of women's nurturing nature according to the passage?

A．It is not inborn in any sense.

B．It is inspired by women’s families.

C．It is caused by social prejudice.

D．It is partly biological in origin.

The Harvard Law School example in paragraph 3 suggests that_________.

A．women are not as competitive as men

B．law is not the fight profession for women

C．women are as excellent as men when they are young

D．academic qualities are not equal to performance

Which of the following statement is true according to paragraph 4?

A．Men leaders should consult colleagues and subordinates more often.

B．Female leaders' success is due to their imitating male leaders.

C．Men and women are different in their leadership style.

D．Decisiveness is an important quality for a successful politician.

It can be inferred from the passage that the writer_________.

A．denies the difference sexes make in real life

B．is prejudiced against men

C．discourages women to be competitive

D．treats sex difference objectively