Which of the following may be the best title for the passage？
A. When Was the Umbrella Invented.
B. The Role of Umbrella in History.
C. The Colors and Shapes of Umbrella.
D. Who Needed Umbrella First.
数据的逻辑独立性是指用户的应用程序与数据库的逻辑结构相互独立，系统中数据逻辑结构改变，应用程序不需改变。（）
【C12】
A. ready
B. doubtful
C. satisfied
D. disappointed
【C8】
A. Oh
B. Well
C. Fire
D. Terrible
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