This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General Considerations - Infectious Diseases, Subject name: Pediatrics
A 5-year-old unimmunized child presented with sore throat & swelling of neck. On examination of throat, the following was seen. What is the most probable causative organism? 
Select and explain. 
A. Streptococcus pyogenes, B. Mycobacterium tuberculosis, C. Staphylococcus aureus, D. Corynebacterium diphtheriae
D: Corynebacterium diphtheriae
Answer: D: Corynebacterium diphtheriae 
Explanation: d. Corynebacterium diphtheriaeA membrane is seen over the tonsil in this child with swelling of neck. Demonstration of bacilli on Albert staining, in the given scenario is suggestive of Diphtheria