Final answer:
Reactivity is a chemical property of matter.
Step-by-step explanation:
Chemical Property of Matter
A chemical property of matter refers to its ability to undergo chemical reactions and form new substances. Out of the given options, reactivity is a chemical property.
For example, when iron reacts with oxygen in the presence of moisture, it forms iron oxide (rust), which is a chemical change.
Density is a physical property that describes how much mass is contained in a given volume of a substance, while magnetism is a physical property related to the attraction or repulsion of certain materials towards a magnetic field. Specific heat is also a physical property that quantifies the amount of heat energy required to raise the temperature of a substance.
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