Which is the most electronegative element?
nitrogen
fluorine
sodium
cesium
hydrogen

Fluorine

Explanation:

As we move from top to bottom in periodic table the electro-negativity will decrease while as we move from left to right in periodic table then the electro-negativity will increase.

So here in all given elements we have to chose the element of first group and towards right in the periodic table.

So out of all given elements the most electro-negative element is Fluorine.

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