Answer:
The statement that is generally true about stable isotopes is:
A. Only I - The nucleus of a stable isotope contains an equal number of neutrons and protons, which helps to maintain the stability of the nucleus.
Statement 2 is not necessarily true for stable isotopes as the nuclear charge and the peripheral charge due to the orbiting electrons may not always be equal and opposite.
Statement 3 is false as stable isotopes do not undergo radioactive decay into more stable isotopes. This is because stable isotopes have a balanced number of protons and neutrons, which results in a stable nucleus that does not decay.
Therefore, the correct answer is A. Only I