Answer:
C. high construction costs
Explanation:
The growth of plants and formation of land mammals characterized the paleozoic era.
Macromolecules are mostly made up of monomers linked into polymers.
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What are macromolecules?</h3>
Macromolecules are made from subunits or building blocks of monomers. These monomers combine with one another through covalent bonds to form larger molecules that are called polymers.
Therefore, macromolecules are made of monomers which are subunits that make up polymer.
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