Our monitor requested that ________. [ ]

A. all the class studied more carefully the problem

B. the problem was more carefully studied

C. with great care the problem could be studied  

D. all the class study the problem more carefully

某公司发行长期债券80000元，债券利息率为8%，筹资费用率为1%，所得税税率为 33%，则长期债券成本率为( )。

A．5.41%

B．8%

C．5.36%

D．9%