A stock’s abnormal rate of return is defined as the:（）

A. expected risk-adjusted rate of return minus the market rate of return.

B. actual rate of return less the expected risk-adjusted rate of return.

C. the market rate of return less the actual rate of return.

（）是为了有效地发现软件缺陷而精心设计的少量测试数据。

A.测试计划

B.测试用例

C.缺陷报告

D.测试报告