单选题 Which of the following statements about the security market line (SML) and capital market line (CML) is most accurate?

A、 The SML is a straight line, but the CML is a curve.
B、 The SML involves the concept of a risk-free asset, but the CML does not.
C、 The SML uses beta, but the CML uses standard deviation as the risk measure.

【正确答案】 C

【答案解析】The SML and CML are both lines, and both intersect the vertical axis at the risk-free rate. The SML describes the risk/return tradeoff for individual securities or portfolios, whereas the CML describes the risk/return tradeoff of various combinations of the market portfolio and a riskless asset.