The principle of risk-return tradeoff means that 风险与收益权衡的原则意味着

A、higher risk investments must earn higher returns. (较高风险的投资必须获得较高的回报。)

B、an investor who takes more risk will earn a higher return. (承担更大风险的投资者将获得更高的回报。)

C、a rational investor will only take on higher risk if he expects a higher return. (理性的投资者只有在期望更高的回报时才会承担更高的风险。)

D、an investor who bought stock in a small corporation five years ago has more money than an investor who bought U.S. Treasury bonds five years ago. (五年前购买小型公司股票的投资者比五年前购买美国国债的投资者拥有更多的钱。)