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.