Mark the correct order of electronegativity
As we move down the group, electronegativity decreases. Electronegativity of fluorine is higher due to its smaller size than chlorine and bromine.
We know that Fluorine is most electronegative element in periodic table, followed by oxygen. On pauling scale, electronegativity of Fluorine is 4.0, Oxygen is 3.5, Chlorine is 3.0 and Bromine is 2.8.
Hence option 1 correct