Which of the following correctly compares cloning and gene therapy?

The right answer is C.

Gene therapy involves introducing the therapeutic gene that will replace the role of the defective gene and, thus, restores the functional capacity of the diseased organ.

The vector production method for gene therapy is a preliminary stage of synthetic biology. As the production of the first vectors has relied mainly on the use of viral sequences existing in nature, this approach is closer to conventional genetic engineering (biotechnology) than to synthetic biology. So gene therapy involves biotechnology.

The term "clone" refers to an object or organization considered to be identical to another.  In biotechnology, cloning refers to the reproduction in the laboratory of genes, cells or organisms from the same original entity.

the backbone of the dna and rna compound is sugar phosphate.