Question

what is a type of matter with its own unique properties that is made of only one type of atom?
element
solution
compound
heterogenous mixture

Explanation:

An element is a pure substance that consists of only one type of atom and has its own unique properties. A solution is a homogeneous mixture. A compound is made up of two or more different types of atoms chemically combined. A heterogeneous mixture has a non - uniform composition.

Answer:

A. Element