Multiple choice general knowledge science & technology Tetanus is caused by Fungus Virus Bacteria Insects Reveal answer Fill a bubble to check yourself C Correct answer Explanation Tetanus is caused by the bacterium Clostridium tetani. The bacteria produce a powerful neurotoxin called tetanospasmin that causes muscle spasms and lockjaw. It is not caused by fungi (A), viruses (B), or insects (D).