What is the type of virus that codes backwards from RNA to DNA?

a. Bacteriophage virus

b. Lysogenic virus

c. Lytic virus

d. Retrovirus

The answer is D.

A retrovirus is any of a group of viruses that characteristically carry their genetic information in form of RNA. These viruses have an enzyme called reverse transcriptase from which they derive their name because they follow the first step of the central dogma backward thus "retro" which means backward.

Reverse transcriptase makes DNA from RNA template thus reversing the usual pattern of transcribing RNA using DNA as the template.

The central dogma of molecular genetics summarizes steps of protein synthesis as DNA → RNA → protein. But retroviruses have modified the process to be RNA → DNA → RNA → protein.