39. A 10-year-old boy is brought to the pediatric clinic with a complaint of a sore throat of 1-week duration. He also has a cough with fevers. He adds that he has pain during swallowing and sometimes water regurgitates from nose when drinking. He was diagnosed with acute tonsillitis by his primary care physician 1month ago, for which he received a week-long course of amoxicillin. His immunization status is unknown. On examination, he is alert and oriented to time, place, and person. On inspection of his oral cavity, an oedematous tongue with a grey-white membrane on the soft palate and tonsils is noted. The neck is diffusely swollen with bilateral tender cervical lymphadenopathy. Which of the following organisms is the cause of this patient's condition and could have been prevented through vaccinations in childhood? a. Streptococcus pyogenes b. Corynebacterium diphtheriae c. Haemophilus influenzae b d. Epstein Barr virus