请教一道GMAT逻辑题

题目

请教一道GMAT逻辑题
2.Which of the following best completes the passage below?
One tax-reform proposal that has gained increasing support in recent years is the flat tax,which would impose a uniform tax rate on incomes at every level.Opponents of the flat tax say that a progressive taxsystem,which levies a higher rate of taxes on higher-income taxpayers,is fairer,placing the greater burden on those better able to bear it.However,the present crazy quilt of tax deductions,exemptions,credits,and loopholes benefits primarily the high-income taxpayer,who is consequently able to reduce his or her effective tax rate,often to a level below that paid by the lower-income taxpayer.Therefore,______
(A) higher-income taxpayers are likely to lend their support to the flat-tax proposal now being considered by Congress
(B) a flat-tax system that allowed no deductions or exemptions would substantially increase actual government revenues
(C) the lower-income taxpayer might well be penalized

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