According to a Blood Test, a Patient Has a Blood

According to a blood test, a patient has a blood iron value of 125 μg/dL.This value means that

A) the sample of blood contains 125 μg of iron.
B) the patient's body contains 125 μg of iron.
C) the mass of iron in the patient's blood is 125 μg.
D) for every deciliter of body volume, the patient contains 125 μg.
E) one deciliter of the patient's blood contains 125 μg of iron.