短文改错。

      Grandma Moses was crazy about painting soon before she picked it up and worked hard at it.

She painted careful and her works were nice.She first painted only to please oneself, and then began

to sell her works with a little money.In 1993, a collector, Louis Caldor happen to see several of

Grandma Moses'work hanging in a shop.He liked them, buying them at once, and set out to look for

less.Caldor held a show to introduce the works of Grandma Moses other artists.Grandma Moses, who

was worldfamous, was died on December 13,1961, at the age of 101.

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在数据库系统中，当数据库的模式改变时，用户程序可以不做改变，这是数据的( )。

A．位置独立性

B．存储独立性

C．逻辑独立性

D．物理独立性