Final answer:
The protein that inserts the DNA copy of HIV's RNA into the chromosome of a cell is called integrase.
Step-by-step explanation:
The protein that can insert the DNA copy of HIV's RNA into the chromosome of a cell is called integrase. Integrase is an enzyme produced by the HIV virus. After the reverse transcriptase builds a complementary DNA strand from the viral RNA template, the double-stranded viral DNA is integrated into the host cell's genome by the integrase enzyme. This integrated viral DNA can then lie dormant or be transcribed to produce new viral RNA and proteins.