<<低压配电设计规范>>规定，在线芯截面减小处、分支处或导体类型、敷设方式或环境条件改变后载流量减小处的线路，当越级切断电路不引起故障线路以外的一、二级负荷的供电中断，且符合下列情况之一时，可不装设短路保护：一、配电线路被前段线路短路保护电器有效的保护，且此线路和其过负载保护电器能承受通过的短路能量；二、配电线路电源侧装有额定电流为20A及以下的保护电器；三、架空配电线路的电源侧装有（）

A.断路保护电器

B.开路保护电器

C.短路保护电器

D.过载保护电器

Jennifer Frye, CFA, is comparing the financial performance of a firm that presents its results under IFRS to that of a firm that complies with U.S. GAAP. The U.S. firm uses the LIFO method for inventory accounting and the other firm uses the FIFO method. If Frye performs the appropriate adjustments to make the U.S. firm’ s financial statements comparable to the firm that reports under IFRS, her adjustments are least likely to change the firm’ s :（）

A. quick ratio.

B. net profit margin.

C. debt-to-equity ratio.