As measures of credit risk, which of the following reflect differences between bond ratings and credit spreads? A. Credit ratings are often more useful in illiquid markets (e.g., municipal bonds) where traders do not observe prices. B. Credit spreads are less accurate than bond ratings as they are based on random market fluctuations rather than research. C. Credit spreads also reflect recovery rates and liquidity premiums, whereas bond ratings do not. D. Bond ratings are issued by institutions, whereas credit spreads result from trading activity