Which statement best explains how graphite and diamond illustrate the limitations of Dalton's third postulate?

• A. Graphite and diamond are compounds formed from carbon and other elements.
• B. Graphite and diamond are isotopes of carbon with different atomic numbers.
• C. Graphite and diamond are different elements with similar atomic masses.
• D. Graphite and diamond are both forms of carbon but have different structures and properties.

Answer: (D)