Which statement is TRUE about Streptococcus pneumoniae and the lung infection it causes?
A) Streptococcus pneumoniae can spread from the focus of infection as a bacteremia. B) Penicillin and erythromycin are the ʺlast chanceʺ drugs for treatment of streptococcal pneumonia. C) Infection with any strain of encapsulated virulent Streptococcus pneumoniae provides long-lasting immunity to all encapsulated virulent strains. D) Streptococcal pneumonia is not as serious as most people think; if left untreated, it usually runs its course in about a week to ten days.