The correct answer is option D- Melanin gene.
All the other options such as ribosomal protein gene, RNA polymerase gene and homeotic gene plays a role in the development of frog embryo, on the contrary melanin gene does not.
Melanin gene activates cells called melanocyets which control the complexion of a skin in organisms. There are multiple colors of skin depending upon the activity of melanin gene present in the body.
