请教一道模考遇到的逻辑题！

selenaly

 When people evade income taxes by not declaring taxable income, a vicious cycle results. Tax evasion forces lawmakers to raise income tax rates, which causes the tax burden on nonevading taxpayers to become heavier. This, in turn, encourages even more taxpayers to evade income taxes by hiding taxable income.

 

The vicious cycle described above could not result unless which of the following were true?

(A) An increase in tax rates tends to function as an incentive for taxpayers to try to increase their pretax incomes.

(B) Some methods for detecting tax evaders, and thus recovering some tax revenue lost through evasion, bring in more than they cost, but their success rate varies from years to year.

(C) When lawmakers establish income tax rates in order to generate a certain level of revenue, they do not allow adequately for revenue that will be lost through evasion.

(D) No one who routinely hides some taxable income can be induced by a lowering of tax rates to stop hiding such income unless fines for evaders are raised at the same time.
            C

(E) Taxpayers do not differ from each other with respect to the rate of taxation that will cause them to evade taxes.
            

答案是c，但是即使知道答案也看不懂是什么意思，请大家给解释一下！谢谢！！

ritachen1214

个人认为选B,对不?

ranning

选C

这是一道假设题，问必然成立

C取非，如果policy maker放任逃税的话，根本就不会制定这样的tax policy了。所以肯定成立

pigscanfly

感觉B也有道理。。。