阅读理解。 Upon reaching an appropriate age (usually between 18 and 21 years), children are encouraged, but not forced, to 'leave the nest' and begin an independent life. After children leave home, they often find social relationship and financial support outside the family. Parents do not arrange marriages for their children, nor do children usually ask permission of their parents to get married. Romantic love is most often the basis for marriage in the United States; young adults meet their future spouses (配偶) through other friends, at jobs,  and in organizations and religious institutions. Although children choose their own spouses, they still hope their parents will approve of their choices. In many families, parents feel that children should make major life decisions by themselves. A parent may try to influence a child to follow a particular profession but the child is free to choose another career. Sometimes children do exactly the opposite of what their parents wish in order to be independent. A son may decide not to go into his father's business on purpose because of a fear that he will lose his autonomy(自主) in his father's workplace. This independence from parents is not an indication that parents and children do not love each other. Strong love between parents and children is universal and this is no exception in the American family. Coexisting (共存) with such love in the American family are cultural values of self - reliance and independence. 1. The writer discusses the marriage of young adults in order to show which of the following? A. They have a strong desire to become independent. B. They want to win the permission of their parents. C. They enjoy the freedom of choosing their spouses. D. They want to challenge the authority of their parents. 2. Most young adults in the U.S. get married because of __________. A. their parents B. financial concern C. love D. family background 3. From the passage we can know that _________. A. American young adults are likely to obey their parents B. most American people never make major decisions for their children C. American young adults possess cultural values of independence D. once a young person steps into his twenties, he will leave his home permanently 4. A son is unwilling to work in his father's business mainly because ________. A. he wishes to make full use of what he has learnt in school B. he wants to prove his independence C. he wishes to do the opposite of what his parents approve of D. he wants to show his love for his parents 5. The main idea of this passage is ________. A. family values B. marriage arrangements C. the pursuit of a career D. decision making