**Correct Option: C. Proton** ### Detailed Explanation: 1. **Understanding Subatomic Particles**: - Atoms are the basic building blocks of matter and consist of three main types of subatomic particles: protons, neutrons, and electrons. - Protons and neutrons are located in the nucleus (the center) of the atom, while electrons orbit around the nucleus. 2. **Charge of Subatomic Particles**: - **Protons**: These particles carry a positive charge (+1). Their presence in the nucleus contributes to the overall positive charge of the nucleus. - **Neutrons**: Neutrons are neutral particles, meaning they have no charge (0). They also reside in the nucleus and help stabilize it by offsetting the repulsive forces between positively charged protons. - **Electrons**: Electrons are negatively charged (-1) particles that orbit the nucleus. They balance the positive charge of protons in a neutral atom. - **Ions**: An ion is not a subatomic particle but rather an atom or molecule that has gained or lost one or more electrons, resulting in a net charge. Ions can be positively charged (cations) or negatively charged (anions). 3. **Why Option C is Correct**: - The question specifically asks for a subatomic particle that has a positive charge and is found in the nucleus. The proton fits this description perfectly as it is positively charged and located in the nucleus of the atom. ### Why the Other Options are Incorrect: - **Option A: Electron**: - Electrons are negatively charged particles and are not found in the nucleus. Instead, they orbit around the nucleus in various energy levels or shells. Therefore, this option does not meet the criteria of being positively charged or located in the nucleus. - **Option B: Neutron**: - Neutrons are neutral particles, meaning they have no charge at all. While they are indeed found in the nucleus, they do not possess a positive charge, which disqualifies this option. - **Option D: Ion**: - An ion is not a subatomic particle but rather a charged atom or molecule. Ions can be either positively or negatively charged depending on the loss or gain of electrons. Since the question asks for a specific subatomic particle with a positive charge, this option is not applicable. ### Summary of Key Points: - Protons are positively charged subatomic particles found in the nucleus of an atom. - Neutrons are neutral and also located in the nucleus, while electrons are negatively charged and orbit the nucleus. - An ion is a charged entity but not a subatomic particle. - The correct answer to the question is C. Proton, as it meets all the specified criteria. ### Revision Summary: - Protons: Positive charge, found in the nucleus. - Neutrons: No charge, found in the nucleus. - Electrons: Negative charge, orbit the nucleus. - Ions: Charged atoms/molecules, not subatomic particles.