Which of the following particles has zero charge ?

The correct answer is Neutrino. Subatomic particles are distinguished by their mass, spin, and electric charge:

• Neutrino: It is an elementary particle with an extremely small mass and zero electric charge. Neutrinos are produced in nuclear reactions (like those in the sun) and interact only via the weak subatomic force and gravity.
• Positron: It is the antiparticle of the electron. It has the same mass as an electron but carries a positive charge of +1e.
• Electron: It is a fundamental subatomic particle that carries a negative electric charge of -1e.
• α-particle: An alpha particle consists of two protons and two neutrons bound together (identical to a helium-4 nucleus). Because it contains two protons and no electrons, it has a positive charge of +2e.