This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteriology, Subject name: Microbiology
Which of the following is true regarding anthrax 
Select and explain. 
A. M' Fadyean reaction shows capsule, B. Human are usually resistant to infection, C. Less than 100 spores can cause pulmonary infection, D. Gram stain shows organism with bulging spores
A: M' Fadyean reaction shows capsule
Answer: A: M' Fadyean reaction shows capsule 
Explanation: M' Fadyean's reaction: When blood films containing anthrax bacilli are stained with polychrome methylene blue for a few seconds and examined under a Microscope, amorphous purplish material is noticed around the bacilli. This represents the capsular material and is characteristic of the anthrax bacilli. Reference: Textbook of Microbiology; Anathanarayan and panicker's; 10th edition; Page no: 251