The answer is "c. Some alleles are dominant and other are recessive"
C. Dinosaur footprint as it is the only body part that is stated in the choices.
Hope this helps :)
The cyanobacteria changed the composition of the earth’s atmosphere by evolving oxygen in what is referred to as the Great Oxygenation Event. This also allowed the ozone to be formed and block off most of the UV rays that are destructive to genetic material. Life was, therefore, also able to exist on land other than in water.
As you talk in animals
nucleus/ plasma membrane / mitochondria
if you talk in plants
nucleus / the cell / plastid / mitochondria
