Answer:
C. LiF, CaCl2, MgO
Explanation:
Ionic compound: It is that compound which consist of negative and position ions and held together by electrostatic force of attraction.
The ionic compound is neutral.
The ionic compound formed between metal and non-metal.
Covalent compound: It is that compound in which sharing of electrons between two atoms occur.
A.
H2O is not ionic compound. It is polar covalent.
Therefore, it does not contain only ionic compounds.
B.CO2,K2O,P4O10
CO2 and P4O10 are not ionic .It is covalent.
Therefore, it does not contain only ionic compounds.
C. LiF,CaCl2 ,MgO
All compounds are ionic because in given compounds one ion is negative and one is metal (positive).
Therefore, it contains only ionic compounds.
D.NO2,MgO,CuCl2
NO2 is not ionic.
Therefore, it does not contain only ionic compounds.
Option C is correct.