Carbon,Diamond and Graphite are together called:___________?

A. Allotrope
B. Isomers
C. Isomorphs
D. Isotopes

The term allotrope refers to one or more forms of a chemical element that occur in the same physical state. … Allotropes may display very different chemical and physical properties. For example, graphite and diamond are both allotropes of carbon that occur in the solid state