（）=负债总额／资产总额。
A.资产比率
B.负债比率
C.负债资产率
D.B和C
参考答案：B
解析：资产负债率又称负债比率。
In the emerging area of biofuels, the problem is both restrictive tariffs and heavy subsidies in rich countries, which drive up food prices and limit export opportunities for efficient developing country producers.
室间隔缺损伴明显肺动脉高压时，如图，其临床表现应除外下列哪一项()
A．右向左分流，出现青紫
B．原有心脏杂音明显增强
C．肺动脉第二音显著亢进
D．肺动脉段明显突出
E．右室压力显著升高
