Final answer:
The prenatal cause of hearing loss in relation to AIDS/HIV is congenital HIV infection, where the virus is transmitted from an untreated mother to her child during pregnancy, childbirth, or breastfeeding.
Step-by-step explanation:
The prenatal cause of hearing loss in relation to AIDS/HIV is most likely due to congenital HIV infection, which occurs when an untreated mother transmits the virus to her child during pregnancy, childbirth, or breastfeeding. Since the transmission of pathogens from one generation to the next is called vertical transmission, and since HIV can lead to various health problems in infants including hearing loss, the correct answer would be congenital HIV infection.