The correct answer is B. PVC.
Addition polymers are formed by the addition of monomers together, without the elimination of any byproducts. The monomers are usually unsaturated hydrocarbons, which means they have double or triple bonds. When these monomers are heated, they react together to form a long chain molecule, or polymer.
Nylon, polythene, and polystyrene are all addition polymers. They are formed by the addition of monomers such as ethylene, styrene, and acrylonitrile, respectively. PVC, on the other hand, is a condensation polymer. Condensation polymers are formed by the reaction of two monomers, with the elimination of a small molecule such as water. In the case of PVC, the monomers are vinyl chloride and ethylene dichloride. When these monomers react together, they form a long chain molecule, and water is eliminated.
Here is a table summarizing the properties of addition and condensation polymers:
| Property | Addition polymer | Condensation polymer |
|—|—|—|
| Monomers | Unsaturated hydrocarbons | Saturated or unsaturated hydrocarbons |
| Reaction | Addition | Condensation |
| Byproduct | None | Water or other small molecule |
| Examples | Nylon, polythene, polystyrene | PVC, polyester, nylon |
I hope this helps! Let me know if you have any other questions.