John is making a model of an atom. He uses three different colors to represent the three basic particles that make up the atom. Which particles should he display in the nucleus of the atom?

Protons and neutrons

Explanation:

The structure of an atom consists of:

Proton: Proton are the particles which carry positive charge. They are present inside the nucleus of an atom.

Neutron: Neutrons carry no charge. They are also present inside the nucleus of an atom.

Electron: Electron can be described as the negative particles of an atom. They are present outside the nucleus of an atom. The electrons orbit around the nucleus of the atom.