The presence of env genes enable retrovirus move from one cell to another. This feature is not present in retrotransposons. Hence, the correct answer is option (c).
Retrovirus encodes at least three different proteins essential for their replication. The three proteins are the products of the genes gag - which have a role in maturation of the RNA (Ribonucleic Acid) genome; pol which encodes the enzyme reverse transcriptase; and env which encodes the structural proteins that make up the protein capsid.
Retrotransposons contain sequences similar to gag and pol, but not env. Due to the absence of genes that are related to env, the retrotransposons cannot leave the cell. Instead, the dsDNA (double stranded Deoxyribo nucleic acid) copies produced by them are inserted back into the genome of the same cell where the transposons are present.
• Both retrotransposons and retrovirus encode reverse transcriptase. Hence, option (a) is not correct
• Both retrotransposons and retrovirus move from one place to another place in a genome. Hence, option (b) is not correct
• As option (c) describes the difference between retrovirus and retrotransposons, option (d) none of the above are correct is false