The answer is B. compound.
An element is composed of only one kind of atom. You cannot separate molecule into simpler substances. For example, hydrogen (H) and oxygen (O) are elements each made of only one atom. Two or more different atoms bonded to one another are a compound. For example, 2 atoms of hydrogen (H) and 1 atom of oxygen are bonded to one another and form water. Thus, water is compound. Mixtures consist of two or more substances that are not chemically combined. Solutions and colloids are mixtures.
