Asubstance that can be broken down into simpler subtend only by a chemical change is aa. homogenous mixtureb. heterogeneous mixturec. elementd. compounde. property

d. compound

Explanation:

Mixture : It is defined as the substance that is made by the combination of two or more different components which are physically combined.

Homogeneous mixture are the mixtures in which the composition of the substances in it are uniformly mixed. Heterogeneous mixture are the mixtures in which the composition of the substances in it are not uniformly mixed.

Compound : It is a pure substance which is made from atoms of different elements combined together in a fixed ratio by mass and are chemically bonded.

Element : It is a pure substance which is composed of atoms of similar elements.

As discussed above,  The different elements in the compounds are chemically bonded and hence, it is the substance which can be broken down into the simpler units when it subtend only by the chemical change.

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