The correct answer is A) Sodium

Electronegativity is a measure of an atom’s ability to attract electrons in a chemical bond. It is generally a periodic trend, with elements on the left side of the periodic table having lower electronegativity than those on the right side.

Additional Information Option Wise

1. Sodium (Na): Sodium is a metal located in group 1 of the periodic table, which is also known as the “alkali metals.” Alkali metals have low electronegativity, meaning that they have a weak attraction for electrons in a chemical bond. This makes them highly reactive and prone to losing electrons, which is why they are typically found in compounds rather than as pure elements.
2. Oxygen (O): Oxygen is a non-metal located in group 16 of the periodic table, which is also known as the “oxygen family.” Oxygen has a relatively high electronegativity of 3.44, meaning that it has a strong attraction for electrons in a chemical bond. This makes it highly reactive and prone to gaining electrons, which is why it is typically found in compounds rather than as a pure element.
3. Magnesium (Mg): Magnesium is a metal located in group 2 of the periodic table, which is also known as the “alkaline earth metals”. Magnesium has a moderate electronegativity of 1.31, which is less than oxygen but more than sodium.
4. Calcium (Ca): Calcium is a metal located in group 2 of the periodic table, which is also known as the “alkaline earth metals”. Calcium has a moderate electronegativity of 1.00, which is less than oxygen, magnesium, and more than sodium.

So, therefore the correct answer is A) Sodium