They have not had a strict system of landownership, one of the universal causes of conflict. They have evolved a system of food-sharing among families that makes the preservation of life possible. The absolute necessity of creating this safeguard against starvation has strengthened bonds between neighbors. Almost every traveler has noted the Eskimos’ friendliness and good humor toward strangers and among themselves. In a country where agriculture is impossible they have been forced to spend their energies in food-gathering rather than warfare. If one family disagreed with another, the usual solution was for that family to pick up its few possessions and go elsewhere. In the vast unused land, moving presented almost no problem. The practice of infanticide, and suicide among the old people, seems to have been a factor of survival in times of food scarcity. The size of the family was controlled to some extent by the ability of the father as a hunter and by the abundance of (猎物) in the area. Marriage was a very serious and lifelong bond among Eskimos; in order to choose a permanent and compatible mate a number of trial marriages were permitted, each lasting perhaps haft a year. During the trial period a couple usually lived with the girl’s parents and the young man hunted exclusively for his future father-in-law. If a child was born as a result of an unsuccessful trial marriage it was adopted by relatives or friends. Children are often given out for adoption in the Eskimos society and are eagerly adopted by other families, for the Eskimos’ camp and (游牧民族的) group represent a kind of extended family. (一夫多妻制) was occasionally practiced by the most successful hunters, but usually to protect a widow or a girl who had lost her father.The Eskimos live peacefully with one another because of ______.

The Eskimos have developed a capacity to live peacefully with one another. They have not had a strict system of landownership, one of the universal causes of conflict. They have evolved a system of food-sharing among families that makes the preservation of life possible. The absolute necessity of creating this safeguard against starvation has strengthened bonds between neighbors. Almost every traveler has noted the Eskimos’ friendliness and good humor toward strangers and among themselves. In a country where agriculture is impossible they have been forced to spend their energies in food-gathering rather than warfare. If one family disagreed with another, the usual solution was for that family to pick up its few possessions and go elsewhere. In the vast unused land, moving presented almost no problem. The practice of infanticide, and suicide among the old people, seems to have been a factor of survival in times of food scarcity. The size of the family was controlled to some extent by the ability of the father as a hunter and by the abundance of (猎物) in the area. Marriage was a very serious and lifelong bond among Eskimos; in order to choose a permanent and compatible mate a number of trial marriages were permitted, each lasting perhaps haft a year. During the trial period a couple usually lived with the girl’s parents and the young man hunted exclusively for his future father-in-law. If a child was born as a result of an unsuccessful trial marriage it was adopted by relatives or friends. Children are often given out for adoption in the Eskimos society and are eagerly adopted by other families, for the Eskimos’ camp and (游牧民族的) group represent a kind of extended family. (一夫多妻制) was occasionally practiced by the most successful hunters, but usually to protect a widow or a girl who had lost her father.The Eskimos live peacefully with one another because of ______. A. their system of landownership B. their system of food-sharingC. the development of agriculture D. their love for moving