If a bond issued by ABC Corporation has been judged by Dominion Bond Rating Service (DBRS) to be "A", which of the following statements is the best way to explain what an "A" rating means?

A) It has been judged to be of the highest quality with minimal risk

B) It has been judged to be upper-medium in quality

C) It has been judged to have certain speculative characteristics

D) It has been judged to be subject to substantial credit risk