What is the smallest chemical particle of an element that retains its properties?

The smallest chemical particle of an element that retains its properties is an atom. Atoms are the fundamental building blocks of matter. Each element on the periodic table is defined by its unique type of atom, which contains protons, neutrons, and electrons. The arrangement and number of these subatomic particles determine the chemical properties and behavior of the element.

Understanding the role of atoms is crucial in fields such as chemistry and biology, as they combine in various ways to form molecules, compounds, and ultimately the materials and substances we encounter. Unlike larger structures like cells, which are comprised of multiple atoms, an atom itself is the most basic unit that preserves the unique characteristics of an element. This is why the correct answer emphasizes the atom's pivotal role in maintaining the properties of the element it represents.