The subscript in the formula should be option c. XY2
Covalent bonding should be the sharing of electrons that lies between atoms. This type of bonding arise that lies between two atoms of the similar element. This bonding should be arise that lies between nonmetals. At the time when the group 1 element and there is a group of 16 element bond so here the subscript should be option c.
Therefore, The subscript in the formula should be option c. XY2
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