问题如下图：
选项：
A. 
B. 
C. 
解释：
老师好，这道题目想跟您确定一下：
reason1：earnings比sales波动更大，是吗？
reason2：earnings比sales更容易被操纵，对吗？
reason3：正确。因为earnings里面考虑了需要付给债权人的利息，也就是考虑了leverage，但是sales没有考虑cost structure，对吗？
NO.PZ201512300100001104 问题如下 4. Cannan’s preferento use the P/E ratio over the P/S ratio is best supporteby: A.Reason 1 B.Reason 2 C.Reason 3 C is correct.The prito sales (P/S) ratio fails to consir fferences in cost structures. Also, while share prireflects the effeof financing on profitability anrisk, sales is a pre-financing income measure anes not incorporate the impaof in the firm’s capitstructure. Earnings refleoperating anfinancileverage, anthus the price-to-earnings (P/E) ratio incorporates the impaof in the firm’s capitstructure. 如题
NO.PZ201512300100001104 为什么不选reason 2?
老师好，想问下解析里为什么说share prireflects the effeof financing on profitability anrisk。股价是如何反应债券融资对利润和风险的影响的呢，公司借债越多，应该是风险越大，但是利润和股价是怎么变化？
Reason 2 Reason 3 C is correct. The prito sales (P/S) ratio fails to consir fferences in cost structures. Also, while share prireflects the effeof financing on profitability anrisk, sales is a pre-financing income measure anes not incorporate the impaof in the firm’s capitstructure. Earnings refleoperating anfinancileverage, anthus the price-to-earnings (P/E) ratio incorporates the impaof in the firm’s capitstructure.我们在讨论FCFF和FCFE的比较时， 有说FCFF 不考虑leverage为什么这道题，考虑了leverage会更优？什么时候考虑leverage更优什么时候不考虑leverage更好？
请问这道题Reason 3要怎么理解呢？
