The word "returns" in paragraph three can be best replaced by "______".

A．they are examples for us on our road to wealth
B．a portfolio is essential to financial success
C．they are really rich people
D．they started out on their own

A．keeping cash is the only way to avoid risks
B．the longer you own a stock, the more you lost
C．the high rate of' profit and high rate of risk coexist in stocks
D．the best way to accumulate wealth is by investing in stocks