Answer:
B
Explanation:
The electronegativity of an atom is a chemical property of that atom that describes the tendency of the atom in question to attract a lone pair of electrons towards itself.
Across the periods, that is going from left to right on the periodic table, it is expected that there is an increase in the electronegativity of elements. Hence, there are more electronegative elements on the right hand side of the periodic table. Thus, we say chlorine or fluorine is more electronegative than either sodium and magnesium.
While it is expected to increase across the period, electronegativity decreases down the group. Hence, we know that chlorine is more electronegative than bromine while fluorine is more electronegative than chlorine. In fact, fluorine is the most electronegative element as it is the first member of the most electronegative group of elements.
Fluorine and oxygen are expected to undergo a covalent bond formation. Both are electron deficient and thus completes their electron orbits by entering into covalent bonding with each other