单选题 An analyst does research about weighted average cost of capital and gathers the following information about a company:
Capital Source Market Value (millions) Before-tax Cost of Capital
Bonds $150 5%
Preferred stock $50 6%
Common stock $300 10%
Based on the information above, if the company's marginal tax rate is 35%, its weighted average cost of capital is closest to:
A. 7.0%
B. 7.6%
C. 8.1%

【正确答案】 B
【答案解析】[解析] 先算出各种资金来源的比例：
Capital Source Weighted
Bonds 150/(150+50+300)=0.3
Preferred stock 50/(100+200+300)=0.1
Common stock 300/(100+200+300)=0.6
WACC=Wd×Kd(1-t)+Wps×Kps+Wce×Kce=0.3×5%×(1-35%)+0.1×6%+0.6 ×10%=7.575%。