What mu st change in an atom for it to become a new element? A. A change of protons B. A change of neutrons C. A change of electrons D. None of the above

The correct answer is A. A change of protons.<br /><br />An atom becomes a new element when there is a change in the number of protons in its nucleus. The number of protons in an atom determines the element to which it belongs. Each element has a unique number of protons, and changing the number of protons results in the formation of a different element.