Without a sufficient dietary intake of vitamin B12, humans will develop vitamin B12 deficiency. Vitamin B12 is found in high concentrations in red meat. Therefore, to prevent vitamin B12 deficiency, humans must eat red meat.

Which of the following is an assumption upon which the support for the above conclusion depends?

A) Humans who do not consume red meat could not prevent vitamin B12 deficiency by using vitamin B12 sysplements.
B) Some plants, such as shitake mushrooms and seaweed, contain high concentrations of vitamin B12.
C) In humans, vitamin B12 is degraded by the acid found in the stomach.
D) Vitamin B12 deficiency can cause a variety of health problems in humans.
E) Because consumption of red meat can cause many health problems, many people avoid consumption of red meat.