The correct option is B HCl
NaOH: The metallic sodium atom is attached to oxygen which is a non-metal. Hence NaOH is an ionic compound due to the high electronegativity difference between sodium and oxygen.
HCl: Hydrogen and chlorine are both nonmetals and hence HCl is a covalent compound.
K2S: Potassium is a metal and sulphur is a non-metal. Therefore, K2S is an ionic compound.
LiH: Lithium is a metal and hydrogen is a non-metal. Therefore, LiH is an ionic compound.
Hence, HCl is the non-ionic compound out of the given compounds.