A Client Has a Suspected Infection by a Particular Microorganism

A client has a suspected infection by a particular microorganism in question that cannot be cultured. Which of the following processes listed below is most likely to result in an accurate diagnosis for the client?

A) Observe directly for the presence or absence of specific antigens in the client's blood serum sample.
B) Introduce cultured, marked antibodies to the client, and observe for a reaction with antigens in the client.
C) Observe for a cytopathic effect on biopsy tissue samples from the client's mucosa.
D) Release purified antigens into the client's circulation to observe whether the client has produced the relevant antibodies.