Which one of the following statements is not true?
A) Nucleons are held together in a nuclide by an electromagnetic force
B) Oxygen-15 is unstable because it has too few neutrons.
C) All nuclides with Z > 83 are unstable and ultimately decay into more stable nuclides with smaller Z values
D) As the atomic number increases, the ratio of neutrons to protons in a nuclide generally increases
E) Generally, the number of neutrons in a nuclide nearly equals the number of protons when the atomic number is small (Z < 18).