The most fundamental group to which a person belo

The most fundamental group to which a person belongs is the family. The institution of the family exists in almost every human culture. It is considered by behavioral scientists to be one of the oldest institutions in human history.

The family unit serves many important functions. The performance of these functions is he reason for the family's importance. Above all , the family serves as a mechanism of species survival (生存，幸存) .

Families also have important economic functions. In primitive societies, the tasks of gathering food and providing shelter were divided among family members. Today, both husband and wife may work and share the duties of homemaking and child rearing.

In addition to its survival and economic functions, the family gives its members social status. In many societies, a person is not considered a complete member until he has married and produced children. Finally, the family helps to meet the basic emotional needs of a person through the love and support received from parents, siblings (兄弟姐妹)， and relatives.

21. Which of the following best states the main idea of the passage？ ____________.

A. The family has changed greatly over time

B. Many of the functions of the family today are being performed by government agencles

C. The most important role for the family is to gather food

D. The family has served many useful functions throughout history

22. According to the passage, which of the following is an example of the role of the family in giving status？____________.

A. A child is taught to respect his elders

B. A couple work for several years to save for the purchase of a home

C. A politician makes a campaign commercial with his family

D. A mother comforts a child after he skins his knees

23. It can be concluded from the passage that the family is ____________.

A. undergoing many changes

B. the only useful social institution

C. likely to exist in future societies

D. not the same today as it was in the past

24. As it is used in the second paragraph of the passage, the word "mechanism" means ____________.

A. parts of an organism or system which work together

B. racial group united by language, religion, custom, etc.

C. the people living in one place, district or country, considered as a whole

D. a worker skilled in using or repairing machines or tools

25. Based on the information in the passage, you can infer that the passage is 一一一一一一·

A. about the family's mechanism of species survival

B. about the social, economic, and emotional usefulness of family throughout human history

C. about duties of the family shared by both husband and wife

D. about the emotional needs received from parents, siblings, and relations