(a) Dacron
Teflon, Polystrene, and PVC are addition polymers. while Dacron (also called Terylene) is a condensation polymer. Condensation polymer is defined as a polymer that is formed by the combination of two or more monomer units and the elimination of water takes place.
In dacron, ethylene glycol and terephthalic acid reacts and removal of water molecule takes place, Hence, dacron is an example of condensation polymer.