Answer:
molecules of elements
Step-by-step explanation:
An element is formed of one type of atoms. An element is a pure substance. A compound is formed of atoms of different elements chemically combined together in fixed ratio. A molecule of compound has different type of atoms chemically combined. For example, a water molecule is of compound having 2 hydrogen atoms and 1 oxygen atom. A molecule of element has same type of atoms chemically combined. For example oxygen O₂ is a molecule of element.
In the given diagram, same atoms are chemically combined. Thus, these represent molecules of elements.