题目内容：
Directions:Thereare2passagesinthissection.Eachpassageisfollowedbysomequestionsorunfinishedstatements.ForeachofthemtherearefourchoicesmarkedA),B),C)andD).YoushoulddecideonthebestchoiceandmarkthecorrespondingletteronAnswerSheet2withasinglelinethroughthecentre．Questionsarebasedonthefollowingpassage．
This passage is primarily concerned with discussing___________．
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