根据短文能容选出最佳选项

Some Americans will fly an American flag outside their house on Saturday. Still, many Americans will not even know it is Flag Day. (71) They do not buy or receive anything. And, as far as we know there are no big stores holding Flag Day sales. Flag Day observes the anniversary of the day Americans first lawmakers approved the design of a new flag for a new nation. The United States of America began as thirteen British colonies.(72）But the colonists fought under a common flag during the Revolutionary War against Britain. lt looked a lot like the American flag today .That flag had thirteen red and white stripes for the thirteen colonies. lt also had a square blue area in the upper left corner.(73) On July fourth ,1776, the American colonists declared their independence.(74) The Continental Congress of the new nation approved a new flag on June fourteenth of the following year.The thirteen red and white stripes remained. Thirteen white stars replaced the British flag inside the blue area. The thirteen stars represented, in the words of Congress, a new constellation. In 1818,Congress approved a law that said a new star would be added to the flag for each new state that joined the union.(75) A. But historians have not been able to decide who made the first American flag. B. Each colony had its own flag . C.They do not get a day off work. D. The United States of American was born. E. Today there are fifty states and fifty whites stars in the blue area of the flag. F.Inside that area were the red cross and white lines of the British flag. G. Most Americans got together with family members and enjoyed a traditional meal. 谢谢老师，祝老师新年快乐

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答案：
71.C
72.B
73.F
74.D
75.E
最终答案：略