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
All of the following statements regarding Clostridium tetani are true, except 
Select and explain. 
A. Spores are resistant to heat, B. Primary immunization consists of three doses, C. Incubation period is 6-10 days, D. Person to person transmission does not occur
A: Spores are resistant to heat
Answer: A: Spores are resistant to heat 
Explanation: The resistance of tetanus spores to heat appears to be subject to strain differences. Most are killed by boiling for 10-15 mins but some resist boiling for up to 3 hrs. Autoclaving at 121degC for 20 mins ensures complete removal of spores. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 265