A)a primary streptococcal infection with Streptococcus pyogenes B)a combination of infection with Streptococcus pyogenes and the rheumatic fever virus C)a secondary streptococcal infection with a different type of streptococcus D)an immunological cross-reaction in which anti-streptococcal antibodies target the heart E)both a primary viral infection and a secondary streptococcal infection