下列哪一种胆汁酸是初级胆汁酸 A．甘氨石胆酸 B．甘氨胆酸 C．牛磺脱氧胆酸 D．牛

罐小者可用于头、面、手、足及皮肤较薄部位的是（）

A．陶瓷罐

B．玻璃罐

C．挤压排气橡胶罐

D．竹罐

E．注射器抽气罐

花生四烯酸在日光作用下可合成（）。

A.维生素C

B.维生素D

C.维生素B

D.维生素E

E.维生素B₁₂

中国的科举制度开始于 ( )

A．明清时期

B．两汉时期

C．隋唐时期

D．魏晋南北朝时期

腹部钝性损伤后，下列不是剖腹探查的适应证的是（）

A.输血后休克又出现

B.腹腔穿刺抽出不凝血液

C.肠鸣音消失，轻度腹胀伴骨盆骨折

D.腹腔内有游离气体

E.有腹膜刺激征

Cooperation is the common endeavor of two or more people to perform a task or reach a jointly cherished goal. Like competition and conflict, there are different forms of cooperation, based on group organization and attitudes.
In the first form, known as primary cooperation, group and individual unite. The group contains nearly all of each individual’s life. The rewards of the group’s work are shared with each member. There is an interlocking identity of individual, group, and task performed. Means and goals become one, for cooperation itself is valued.
While primary cooperation is most often characteristic of preliterate societies, secondary cooperation is characteristic of many modern societies. In secondary cooperation, individuals devote only part of their lives to the group. Cooperation itself is not a value. Most members of the group feel loyalty, but the welfare of the group is not the first consideration. Members perform tasks so that they can separately enjoy the fruits of their cooperation in the form of salary, prestige, or power. Business offices and professional athletic teams are examples of secondary cooperation.
In the third type, called tertiary cooperation or accommodation, latent conflict underlies the shared work. The attitudes of the cooperating parties are purely opportunistic; the organization is loose and fragile. Accommodation involves common means to achieve antagonistic goals; it breaks down when the common means cease to aid each party in reaching its goals. This is not, strictly speaking, cooperation at all, and hence the somewhat contradictory term antagonistic cooperation is sometimes used for this relationship.

Which of the following statements about primary cooperation is supported by information in the passage

A. It was limited in prehistoric times.
B. It is usually the first stage of cooperation achieved by a group of individuals attempting to cooperate.
C. It is an ideal that can never be achieved.
D. It is most commonly seen among people who have not yet developed reading and writing skills.