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Which of the following statements is not true regarding bond ratings? The ratings assigned are meant to indicate the probability of default for the bond issuer. are considered investment D The bonds assigned one of the grade bonds. Once a rating is assigned to an issue it cannot be changed for the first two years after which it is reviewed on a regular basis. Bonds rated BB and below are referred to as high yield or "junk" bonds. 03 signs or numbers after the The rating agencies modify the ratings with + and letters