How Are Antibodies Other Your Own Used to Help Fight

How are antibodies other your own used to help fight an infection?

A) They are engineered in the lab to behave like your own antibodies and can be used instead.
B) They are isolated from someone else and used as a supplement to the patient's own immune system.
C) They can be injected and will function like memory cells, preventing future infections.
D) They are concentrated from animals who have been infected with a particular disease and used to supplement a sick person's immune system response.
E) All of the above