Polymer obtained by the condensation polymerization is

Options

A. polythene
B. teflon
C. phenol-formaldehyde resin
D. nitrile rubber.

Explanation

To determine the polymer obtained by condensation polymerization from the given options (polythene, Teflon, phenol formaldehyde resin, and nitrile rubber), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Polymerization**:
- There are two main types of polymerization: addition polymerization and condensation polymerization.
- In **addition polymerization**, monomer units combine without the loss of any small molecules.
- In **condensation polymerization**, monomer units combine with the elimination of small molecules such as water, ammonia, etc.

2. **Analyze the Given Polymers**:
- **Polythene**: This is made from the polymerization of ethylene (C2H4) through addition polymerization. No small molecules are eliminated.
- **Teflon**: This is made from the polymerization of tetrafluoroethylene (CF2=CF2) and also involves addition polymerization.
- **Phenol Formaldehyde Resin**: This is synthesized from phenol and formaldehyde through a condensation reaction, where water is eliminated during the formation of the polymer.
- **Nitrile Rubber**: This is produced from the polymerization of acrylonitrile and other monomers, typically through addition polymerization.

3. **Identify the Correct Polymer**:
- Since we are looking for a polymer that is obtained through condensation polymerization, we focus on the phenol formaldehyde resin.
- The reaction involves the combination of phenol and formaldehyde, resulting in the elimination of water (a small molecule), which is characteristic of condensation polymerization.

4. **Conclusion**:
- The polymer obtained by condensation polymerization from the options provided is **phenol formaldehyde resin**.

### Final Answer:
The polymer obtained by condensation polymerization is **phenol formaldehyde resin**.

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