What is a proton?

A proton is defined as a positively charged subatomic particle located in the nucleus of an atom. Protons play a critical role in determining the identity of an element; the number of protons in an atom’s nucleus defines what element it is. For instance, hydrogen has one proton, while helium has two.

In relation to the context of the other options, negatively charged particles in atoms refer to electrons, which orbit the nucleus rather than reside within it. Neutral particles found in the nucleus are known as neutrons, which also contribute to the atomic mass but do not affect the atomic number or overall charge of the atom. The option depicting particles that conduct electricity is too vague and can refer to various charge carriers in different substances, and does not specifically define any type of subatomic particle.

Thus, identifying protons as positively charged subatomic particles in the nucleus is accurate and highlights their fundamental role in atomic structure.