John's success has nothing to do with good luck. It is years of hard work      has made him what he is today.

A．why

B．when

C．which

D．that

在使用内部报酬率法进行固定资产投资决策时，方案可行的标准是内部报酬率要（）

A．小于或等于资本成本率

B．大于或等于资本成本率

C．大于或等于标准离差率

D．小于或等于标准离差率