EVERYDAY SCIENCE

Detailed explanation-1: -The correct option is A Element. An element is defined as a pure substance made up of only one kind of atoms that cannot be converted into anything simpler than itself by any physical or chemical process.

Detailed explanation-2: -Element : A pure substance composed of the same type of atom throughout.

Detailed explanation-3: -Answer and Explanation: An element is considered a pure substance because it is composed of only one type of atom. Every atom of that element will have the exact same number of protons in the nucleus and will exhibit the same primary chemical properties.

Detailed explanation-4: -Chemically pure and isotopically pure In chemistry, a pure element means a substance whose atoms all (or in practice almost all) have the same atomic number, or number of protons. Nuclear scientists, however, define a pure element as one that consists of only one stable isotope.