What is the most likely reason for the development of a vitamin B₁₂ deficiency?

Question

Quizplus · Accepted Answer

Vitamin B₁₂ is primarily absorbed in the ileum of the small intestine and requires intrinsic factor, a protein made in the stomach, for proper absorption. Conditions that affect the ileum, such as Crohn's disease or surgical removal, or those that affect intrinsic factor production, such as pernicious anemia, can lead to inadequate absorption and the development of a vitamin B₁₂ deficiency.

What Is the Most Likely Reason for the Development of a Vitamin