Its D. combustibillaty
A. density is how hard or densely the substances molecules are together
B.boiling point is the point at which bonds that hold molecules are broken and so the substances boils
C. malleability is how easily a substance can be stretched until it breaks
D. is a chemical property of how much chemical energy is stored in a substance for it to combust
hope that helps
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I believe the atomic level increases hope this helps.
I believe the correct answer from the choices listed above is the second option. The pair of elements that is most likely to chemically combine and form ionic bonds would be <span>lithium and chlorine. Lithium is metal and chlorine is nonmetal which as a compound forms ionic bonds. Hope this answers the question.</span>