Some species of cats exhibit a color pattern where the torso is lighter in color while the extremities tend to show darker colors from melanin expression. Each of the cells in these cats has the same DNA. Which of the following best explains how it is possible for the coloration to differ in each area of the body? A The DNA in the extremities has mutated.
B The DNA coding for melanin is missing from the cells found in the torso.
C Cooler parts of the body express genes that are not expressed in warmer parts.
D All genes in cats are expressed equally

I need help I'm testing this is my finals

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."