Microbiology Clostridium botulinum toxin mode of action is by: March 2012 A Presynaptic block B Postsvnaptic block C Competitive inhibition of acetylcholine D Destruction of acetylcholine 💡 Explanation Clostridium botulinum toxin mode of action is by: March 2012 ✓ Correct Answer: A. Presynaptic block