Why is it important to know a person's rhesus factor before a blood transfusion?
a patient who is rh+ can receive only rh– blood.
a patient who is rh– can receive only rh+ blood.
a patient who is rh+ can receive only rh+ blood.
a patient who is rh– can receive only rh– blood.

Answer;

Rh- blood can only receive Rh- blood.

Explanation;

-Rhesus factor is a type of antigens on the surface of red blood cells, beside the antigens of blood groups , Humans are classified according to the presence of Rhesus factor in their blood into Positive Rhesus factor (Rh+) and Negative Rhesus factor (Rh−).

- When it comes to blood transfusion, anyone who is Rh positive can receive blood from someone who is Rh negative, but those with negative blood types cannot receive from anyone with a positive blood type.

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