15. POLYMERS (HM)
Explanation:
Condensation polymers are any kind of polymers formed through a condensation reaction, where molecules join together and lose small molecules as by-products such as water or methanol. Polyethylene is made by the addition polymerization of ethylene (olefin) monomers. Polyvinyl chloride is produced by polymerization of the vinyl chloride monomer. Orlon is a polymer of vinyl cyanide. It is made by the addition of acrylonitrile molecules. Terylene is a synthetic polyester fiber produced by polymerizing ethylene glycol and terephthalic acid with the removal of water.