<prompt> A person working in an abattoir presented with malignant pustule on hand; What is the causative agentClostridium botulinumClostridium perfringensStreptococcus pyogenesBacillus anthracis  <response>: Clinical clue here are: Abattoir who has contact with animal products; Classical malignant pustule is seen in Anthrax. It occurs usually in face and neck A papule is seen at the site of entry followed by vesicle and necrotic ulcer. The lesion characteristic of cutaneous anthrax is central black eschar; this lesion is called as malignant pustule. Ref:- Ananthanarayan and Panikers Textbook of Microbiology 10th ed; Pg num:- 250 