A.The weak force acts within protons and neutrons, and the electromagnetic force has an infinite range.
Explanation:
Weak force explanis the interaction among subatomic particles (e.g. protons and neutrons) and is directly involved in the radioactive decay of the atoms. This is the reason that it has been well studied to understand nuclear fission reactions. Its range is very limited and does not exceeds beyond subatomic particles.
On the other hand, electromagnetic force is a very strong force that holds atoms together. It has infinite range. Once can assume the strength of this force from the basic understanding that, within an atom, electrons and protons exist together despite of their opposite charges. Nevertheless, the integrity of atom is not disturbed.
