Final answer:
Vomiting is the least characteristic symptom of Clostridium perfringens food poisoning, which is usually associated with abdominal cramps and watery diarrhea.
Step-by-step explanation:
The least characteristic symptom of Clostridium perfringens food poisoning is vomiting. While symptoms of foodborne diseases often include nausea and vomiting, vomiting is not typically associated with Clostridium perfringens food poisoning. Instead, the key symptoms of this type of food poisoning are abdominal cramps and watery diarrhea. Some severe cases of Clostridium perfringens food poisoning may also cause hemorrhaging, pain, and bloating.