Robert, a Young Social Worker, Works Among HIV/AIDS Patients and Always

Robert, a young social worker, works among HIV/AIDS patients and always has a chance to contract HIV if he comes in contact with bodily fluids of the patients. In order to prevent an HIV infection, he takes a drug that helps stop HIV from taking hold and spreading in his body. In the context of prevention and treatment of HIV, identify the method of prevention used by Robert in this scenario.

A) pre-exposure prophylaxis (PrEP)
B) consolidation therapy
C) spiritual self-schema therapy (3-S therapy)
D) post-exposure prophylaxis (PEP)