AIDS or acquired immuno deficiency syndrome, caused by human-immunodeficiency virus or HIV.
In 1983, a group of scientists isolated a virus from AIDS patient, which was strikingly similar in shape to the other Human T-lymphotropic viruses (HTLV) and so this newly isolated virus was called HTLV-III.
Another group of scientists, at the same time, named this isolated virus as lymphadenopathy-associated virus or LAV. As these two virsues turned out to be the same, in 1986, LAV and HTLV-III were renamed as HIV.
Thus, the correct answer is option (B), 'HTLV-III'.