The correct option is A Staphylococcal enterotoxin
Staphylococcal enterotoxin (enterotoxin is a toxin produced in or affecting the intestines) is a toxin excreted by the bacterium Staphylococcus aureus. It is a leading agent that thrives on unrefrigerated meat, dairy and bakery products and is responsible for food poisoning. Thus the correct answer is option A.