Which of the following subatomic particles always has a positive charge?

• A. Alpha particle
• B. Neutron
• C. Proton
• D. Electron

Answer: (C)

Verified step by step guidance

1. Recall the basic charges of common subatomic particles: a proton has a positive charge, an electron has a negative charge, and a neutron has no charge (neutral).
2. Understand that an alpha particle is composed of 2 protons and 2 neutrons, so it carries a positive charge overall but is not a single subatomic particle.
3. Identify that the question asks for a subatomic particle that always has a positive charge, which means it must be a fundamental particle, not a composite one like the alpha particle.
4. Compare the options: proton (positive charge), neutron (neutral), electron (negative charge), and alpha particle (composite with positive charge).
5. Conclude that the proton is the only fundamental subatomic particle listed that always carries a positive charge.