Questão 84

Most people believe they know what actually causes AIDS. For a decade, scientists, government officials, journalists, TV shows, and others have told them that AIDS is caused by a retrovirus called HIV. This virus supposedly infects and kills the “T-cells” of the immune system, leading to a fatal immune deficiency after an asymptomatic period that averages 10 years. Most people do not know - because there has been a visual media blackout on the subject - about a scientific controversy over the cause of AIDS. Leading biochemical scientists have been warning for years that there is no proof that HIV causes AIDS. The warnings were met first with silence, then with ridicule and contempt. For example, some scientists compared the doubters to people who think that bad air causes malaria.

(What Causes Aids?, Charles A. Thomas et al. Adaptado)

Na terceira linha do texto, a palavra them refere-se a