Correct the mistakes in the following sentences. Underline the wrong parts and put the correct ones in the brackets.(10%) When overall exports exceed imports, a country said to have a trade surplus.

A．analyze the impact that slavery had on African political and economic systems
B．Review the attempt of recent scholarship to study the influence of African music on other music
C．Correct the failure of some scholarship to appreciate the significance of music in African culture
D．Survey the ways by which people attempt to preserve their culture against the effects of oppression

A．rapidly changing
B．cyclically recurring
C．steadily growing
D．unrelated to change in technology