<prompt> Which of the following is true about Clostridium tetani?It is an aerobe that forms surface growth where the oxygen tension is more than 2mmHgIt has drum stick appearanceIt does not show any hemolysisIt is prominently seen in winter and dry atmosphere  <response>: The clostridia are large anaerobic, gram-positive, motile rods. Their natural habitat is the soil, marine sediments, sewage, or the intestinal tract of animals and humans, where they live as saprophytesClostridia are anaerobes and grow under anaerobic conditions; a few species are aerotolerant and also grow in ambient air.In general, the clostridia grow well on the blood-enriched mediaClostridium tetaniIt is Gram-positive, and its appearance on a gram stain resembles tennis rackets or drumsticks.Reference: Jawetz, Melnick, Adelbergs Medical Microbiology; 27th edition; Chapter 11; Spore-Forming Gram-Positive Bacilli: Bacillus and Clostridium Species 