Which of the following subatomic particles has the largest mass?

• A. Positron
• B. Neutron
• C. Electron
• D. Proton

Answer: (B)

Verified step by step guidance

1. Recall the three main subatomic particles: electron, proton, and neutron, and also consider the positron, which is the electron's antiparticle.
2. Understand that the mass of a particle is a fundamental property and is usually compared relative to the mass of a proton or neutron, which are roughly similar in mass.
3. Know that the electron and positron have much smaller masses compared to protons and neutrons; specifically, the electron and positron masses are about 1/1836 the mass of a proton.
4. Recognize that the proton and neutron have masses close to 1 atomic mass unit (amu), but the neutron is slightly heavier than the proton.
5. Conclude that among the given particles, the neutron has the largest mass because it is slightly heavier than the proton, and both are much heavier than the electron and positron.