Answer:
Monomers.
Explanation:
The polymers are present in the living organisms. These polymers forms the important biomolecules of the living organism. Different chemicals are also prepared by the polymerization reaction.
Monomers are the single unit that are repeated several times to form a polymers. The polymers are formed by the reduction of the small molecules like water, ethers and alcohol. Monomers are the repeating structural units of polymers.
Thus, the correct answer is monomers.