Which of the following are likely to form a covalent bond? A) gold and gold. B) oxygen and oxygen. C) magnesium and oxygen. D) magnesium and gold

Covalent bonds exists between non - metals acting as both anion and cation. In this type of bond, the valence electrons are shared between the atoms. Among the choices, covalent bonds exist in B) oxygen and oxygen. This is a non-polar covalent compound because of the equal sharing of valence electrons.