This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteria, Subject name: Microbiology
A 45 year old veterinary surgeon presented with a black eschar on the left hand. There was extensive swelling around the ulcer but it was not painful. There were few vesicular lesions surrounding the ulcer. He presented a history of injury to the hand while handling animals. What would be the presumptive diagnosis on the basis of history and culture smear of fluid from the vesicles? 
Select and explain. 
A. Actinomycetoma, B. Clostridium infection, C. Cutaneous anthrax, D. Extrapulmonary nocardiosis
C: Cutaneous anthrax
Answer: C: Cutaneous anthrax 
Explanation: Ans. is 'c' i.e., Cutaneous AnthraxImage description - Gram stain of culture smear of B. anthracis showing gram +ve bacilli (Bamboo stick appearance).