Electronegativity quantifies an atom's propensity to draw electrons toward itself within a chemical bond. The Pauling scale is the most prevalent measure for this property.
Let's examine the electronegativity of each provided element:
- Sodium (Na): Electronegativity ≈ 0.93
- Fluorine (F): Electronegativity ≈ 3.98
- Oxygen (O): Electronegativity ≈ 3.44
- Chlorine (Cl): Electronegativity ≈ 3.16
Based on these values, fluorine exhibits the highest electronegativity at 3.98. As the most electronegative element on the periodic table, fluorine possesses a strong ability to attract electrons in chemical bonds.
Consequently, fluorine is the element with the greatest electronegativity among the given choices.