Which of the following correctly describes the genome of HIV?

The correct answer is Option (2) → RNA, enclosed in an envelope

HIV, the virus that causes AIDS, belongs to a group of viruses called retroviruses. A retrovirus has an envelope that encloses its RNA genome. Inside a host cell, this RNA is copied into viral DNA by the enzyme reverse transcriptase.

Option (1) DNA, enclosed in an envelope — Incorrect. The genome of HIV is not DNA. DNA is made from the viral RNA only after the virus has entered a host cell.

Option (2) RNA, enclosed in an envelope — Correct. HIV has an RNA genome, and an envelope encloses it, as in all retroviruses.

Option (3) DNA, without an envelope — Incorrect. Both parts are wrong: the genome is RNA, and HIV does have an envelope.

Option (4) RNA, without an envelope — Incorrect. The genome is RNA, but HIV is not a naked virus; its RNA genome is enclosed in an envelope.

NCERT Extract:
AIDS – “… AIDS is caused by the Human Immuno deficiency Virus (HIV), a member of a group of viruses called retrovirus, which have an envelope enclosing the RNA genome (Figure 7.6). Transmission of HIV-infection generally occurs by (a) sexual contact with infected person, (b) by transfusion of contaminated blood and blood products, (c) by sharing infected needles as in the case of intravenous drug abusers and (d) from infected mother to her child through placenta.”

Figure 7.6 Replication of retrovirus