Which of the following statements is NOT a reason for the versatile nature of carbon?

The statement that is NOT a reason for the versatile nature of carbon is 'Carbon can form ionic bonds with itself.' Carbon usually forms covalent bonds, not ionic ones. It has four valence electrons, so it shares them (tetravalency). Carbon atoms also join to one another in long chains (catenation). For these reasons, carbon almost never forms ionic bonds with itself or other elements.