What is the definition of electronegativity?

A.     The relative measure of the tendency of an atom when bonded in a molecule to attract a shared pair of electrons towards itself.

B.     The minimum energy required to remove a mole of electrons from a mole of gaseous atoms.

C.     The enthalpy change occurring in \({\text{kJ mo}}{{\text{l}}^{ - {\text{1}}}}\) when a gaseous atom gains one electron to form a negative ion.

D.     The strength of an atom measured in \({\text{kJ mo}}{{\text{l}}^{ - {\text{1}}}}\) to attract an electron to itself when bonded in a molecule.

A