You are answering a USMLE-style medical question. Question: An investigator is studying the growth pattern of a particular bacterial strain that caused a respiratory disease outbreak in children in rural Venezuela. The bacteria are found to be able to grow in a specialized culture that contains sheep blood, cystine, and potassium tellurite; the colonies are black and have a shining surface. The isolated bacteria are most likely which of the following? Options: A) Legionella pneumophila B) Haemophilus influenzae C) Bordetella pertussis D) Corynebacterium diphtheriae Reply with ONLY the letter of the correct answer (A, B, C, or D). No explanation.