Below Are Four Compounds

Below are four compounds.Choose the statement below that BEST describes these four. ​
CH₂O Ti₂O₃ MgO H₂O
I II III IV
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A) All of these are ionic compounds.
B) I and II are covalent molecules, whereas III and IV are ionic.
C) II and III are ionic, whereas I and IV are covalent.
D) I, III, and IV are covalent, whereas II is ionic.
E) All of these are covalent molecules.