单选题 Which category of tests assumes that, in an efficient market, securities lie on the security market line?

A、

A. Event studies.
B、

B. Cross-sectional tests.
C、

C. Time-series tests.

【正确答案】 B

【答案解析】Cross-sectional tests operate under the assumption that, in an efficient market, all securities must lie directly on the security market line.