Which One of the Following Statements Is Correct Based on the Historical

Which one of the following statements is correct based on the historical record for the period 1926-2007?

A) The standard deviation of returns for small-company stocks was double that of large-company stocks.
B) U.S.Treasury bills had a zero standard deviation of returns because they are considered to be risk-free.
C) Long-term government bonds had a lower return but a higher standard deviation on average than did long-term corporate bonds.
D) Inflation was less volatile than the returns on U.S.Treasury bills.
E) Long-term government bonds underperformed intermediate-term government bonds.