Electronegativity is :
a) electronegativity is the negative charge surrounding the nucleus of an atom.
b) the number of electrons in the outermost electron shell.
c) the attraction of an atom for the electrons in a covalent bond.
d) the repulsion of electrons in one atom for electrons in another atom.

c) the attraction of an atom for the electrons in a covalent bond.

Explanation:

Electronegativity, symbol χ, is a chemical property describing an atom's ability of to attract a shared pair of electrons to itself. It is influenced by the atomic number of the atom and the distance between the valence electrons and the charged nucleus. As the electronegativity number of atoms increases, the more the atom attracts electrons towards itself.

14 days is the half-life of phosphorus-32