The Rationale for Administering Injections of Vitamin B12 to Patients

The rationale for administering injections of vitamin B12 to patients with pernicious anemia is that:

A) The patient's body does not normally manufacture enough vitamin B12.
B) The patient may lack the intrinsic factor necessary for vitamin B12 absorption.
C) Vitamin B₁₂ is found in very small quantities in the patient's body.
D) Vitamin B₁₂ is a mineral necessary to aid in the formation of strong bones.