Electronegativity quantifies an atom's propensity to draw shared electrons within a covalent bond. This property generally rises across a period and declines down a group in the periodic table. Fluorine, positioned at the upper right (excluding noble gases), exhibits the maximum electronegativity at 3.98 on the Pauling scale. Comparative values: (a) Oxygen (3.44) possesses a high electronegativity, though it is lower than fluorine's.
(b) Nitrogen (3.04) has a lower electronegativity.
(d) Chlorine (3.16) is electronegative among halogens but still ranks below fluorine.