Exons, because they are the only coding regions in the DNA.
Hope this is helpful!
A mutation is a change in trait. For example people who are lactose intolerant are normal, but people that can can drink milk without a problem have mutated. Hopefully this makes sense and helped.
Im pretty sure if it has a wall it is a plant, if it has a nuclear membrane it is a eukaryotic
D. nRNA... hope it helps :)
