Answer:
The correct answer is option b, that is, atom.
Explanation:
The basic unit of all matter is an atom. The matter can be an element that possesses a solitary kind of atom within it as golf refers to an element that possesses a single type of atom with similar atomic numbers. A matter can be a compound that exhibits two or more types of atoms like water. The proton, neutron, and the electron are all considered as the sub-atomic particles. The electrons revolve around a central unit of atom called nucleus. The nucleus possesses both neutrons and protons.
