A nurse is talking with a client who has to come to the clinic for HIV testing. The nurse should explain to the client that after the laboratory has the enzyme immunoassay (EIA) results, it will use which of the following tests to confirm the diagnosis?

A. Viral load test: Viral load testing measures the amount of HIV RNA in the blood to monitor disease progression and response to antiretroviral therapy. It is not used as a confirmatory diagnostic test following a positive EIA result. B. Western blot assay: The Western blot assay is used to confirm a positive enzyme immunoassay (EIA) result. It detects specific antibodies to HIV proteins, providing a definitive diagnosis by verifying the presence of HIV antibodies and reducing the risk of false-positive results. C. CD4+ T-cell count: CD4+ T-cell counts assess immune system function and help determine disease stage and treatment planning in clients with HIV. This test does not confirm an HIV diagnosis and is used for monitoring rather than initial confirmation. D. Quantitative RNA assay: Quantitative RNA assays measure the level of HIV RNA in the bloodstream, primarily to monitor treatment effectiveness or early infection. It is not the standard confirmatory test following an initial EIA.