A Stool Sample from the Patient Is Cultured, and Confirms

A stool sample from the patient is cultured, and confirms the presence of Clostridium botulinum. In addition, the stool sample as well as leftover stew and green beans are tested for botulinum toxin—toxin is present in the green beans and in the stool sample, but not in the stew. These results confirm the diagnosis of foodborne botulism. You are one of the RNs taking care of the patient—he remains in the hospital for several weeks, before being discharged.
-Why would the home-canned green beans rather than the tomato-beef stew be a possible source of C. botulinum?

A) Beans are low-acid. Any C. botulinum endospores that survived the home-canning process could germinate in the cans, giving rise to vegetative cells that produce botulinum toxin. 
B) Canning creates an anaerobic environment. Any spores surviving the canning process could germinate, giving rise to vegetative cells that produce botulinum toxin.
C) The acidic pH of the tomato-beef stew would likely inhibit that growth of vegetative Clostridium botulinum cells. Low-acidity beans would not inhibit the growth of these cells.
D) The tomato-beef stew was not canned. The presence of oxygen in this food would prevent the growth of Clostridium botulinum, which is a obligate anaerobe.
E) All of the answer choices are correct.