Elements in the same group have… A. A wide range of chemical properties
B. The same atomic radius
C. Number of electrons in its outer shell.
D. Same number of protons
E. The same number of electron shells.

the skeletons of most mammals reach a certain size and then stop growing. however, many animals, including some mammals, keep growing throughout their lives. kangaroos, for example, just keep growing and growing until they die. also, the longer an animal lives the greater the chance it might catch some deadly disease.