We have known for a long time that the organization of any particular society is influenced by the definition of the sexes and the distinction drawn between them. But we have realized only recently that the identity of each sex is not so easy to pin down, and that definitions evolve in accordance with different types of culture known to us, that is, scientific discoveries and ideological revolutions. Our nature is not considered as immutable, either socially or biologically. As we approach the beginning of the 21st century, the substantial progress made in biology and genetics is radically challenging the roles, responsibilities and specific characteristics attributed to each sex, and yet, scarcely twenty years ago, these were thought to be "beyond dispute".
We can safely say, with a few minor exceptions, that the definition of the sexes and their respective functions remained unchanged in the West from the beginning of the 19tb century to the 1960s. The role distinction, raised in some cases to the status of uncompromising dualism on a ply hierarchical model, lasted throughout this period, appealing for its justification to nature, religion and customs alleged to have existed since the dawn of time. The woman bore children and took care of the home. The man set out tc conquer the world and was responsible for the survival of his family, by satisfying their needs in peacetime and going to war when necessary.
The entire world order rested on the divergence of the sexes. Any overlapping or confusion between the roles was seen as a threat to the time-honored order of things. It was felt to be against nature, a deviation from the norm.
Sex roles were determined according to the "place" appropriate to each. Women’s place was, first and foremost, in the home. The outside world, i.e. workshops, factories and business firms, belonged to men. This sex-based division of the world (private and public) gave rise to a strict dichotomy between the attitudes, which conferred on each its special identity. The woman, sequestered at home, "cared, nurtured and conserved". To do this, she had no need to be daring, ambitious, tough or competitive. The man, on the other hand, competing with his fellow men, was caught up every day in the struggle for survival, and hence developed those characteristics which were thought natural in a man.
Today, many women go out to work, and their reasons for doing so have changed considerably. Besides, the traditional financial incentives, we find ambition and personal fulfillment motivating those in the most favorable circumstances, and the wish to have a social life and to get out of their domestic isolation influencing others. Above all, for all women, work is invariably connected with the desire for independence.
According to the fourth paragraph, the author seems to think that（）
A.female passivity is natural
B. men and women are physically identical
C. men are born competitive and aggressive
D. some different sex identity is acquired