Which of the following correctly describes a neutron?

A neutron is defined as a non-charged particle found within the nucleus of an atom. Neutrons play a crucial role in contributing to the atomic mass and stabilizing the nucleus alongside protons, which are positively charged. This balance is essential because it helps prevent the repulsion between positively charged protons, which could otherwise destabilize the nucleus.

The other options incorrectly characterize the neutron. For instance, neutrons are not positively charged or negatively charged, so describing them as a positively or negatively charged particle is inaccurate. Furthermore, the concept of particles orbiting around the nucleus typically refers to electrons, which are indeed negatively charged and exist in specific energy levels outside the nucleus. Understanding the properties and roles of neutrons helps clarify their importance in atomic structure and stability.