阅读理解 　　Economics can render service in the area of exchange, but its tools find less purpose when applied to paradigms dominated by alternative models of transactions and social relationships. In small groups gift-giving is substituted Line for the role of exchange, which entails obligation: people receiving gifts are expected to reciprocate in the future and this reciprocity binds small groups together, whereas exchange rarely does so. Two people exchange only when both benefit, neither incurring a social obligation as a result, and where social obligations exist, exchange may not work well. Exchange nevertheless allows for extremely complex interactions among strangers: when employing a product, a consumer benefits from the efforts of hundreds of anonymous people who have contributed to that commodity. Such analysis also has its limits in the case of an area such as government, for economics seeks regularities in social life, which are more likely to occur when no one individual has an appreciable effect on the group.

单选题 Which of the following might serve as the most appropriate title for the passage?

单选题 It can be inferred from the passage that economic theory as it presently stands would most likely apply to which of the following situations?

单选题 According to the passage, the dynamics of small group economies differ from those of large group economies in that________.

单选题 Which of the following best describes the organization of the passage?