The right options are;
-They’re made up of more than one substance.
-They’re readily available in nature.
Composite materials are materials that are produced by combining two or more substances that has different properties. Composite materials have unique properties that are different from the individual constituents and the constituents can be easily differentiated within the composite materials because they do not blend into each other. Some composite materials are readily available in nature. For example wood is a composite material that is composed of cellulose and lignin.
