Which of the following particles carries a positive charge?

The particle that carries a positive charge is the proton. Protons are fundamental components of atomic structure, residing in the nucleus alongside neutrons. Each proton has a positive electric charge equal in magnitude to the negative charge of an electron, which is why they are essential for balancing the overall charge of an atom. The presence of protons defines the element and its position on the periodic table, directly influencing its chemical properties.

While the other choices include particles such as electrons, which carry a negative charge, and neutrons, which have no charge, the proton stands out due to its specific positive charge. Ions are charged particles resulting from the loss or gain of electrons, but they are not inherently positive; they can be either positively charged (cations) or negatively charged (anions) depending on their electron balance. Thus, in the context of the question, it is the proton that uniquely fulfills the requirement of carrying a positive charge.