Polymer obtained by condensation polymerisation is:

Options

A. Polythene
B. Tefflon
C. Phenol-formaldehyde
D. Nitrite rubber

Answer

To determine which polymer is obtained by condensation polymerization, we need to analyze the options provided:

1. **Understanding Polymerization Types**:
- **Addition Polymerization**: In this process, monomers with unsaturated bonds (like alkenes) join together without the loss of any small molecules (by-products). Examples include polythene and teflon.
- **Condensation Polymerization**: This involves the reaction of monomers with two or more functional groups, resulting in the formation of a polymer along with the elimination of a small molecule (like water or methanol).

2. **Analyzing the Options**:
- **Option A: Polythene** - This is formed through addition polymerization, where ethylene monomers join together without any by-product.
- **Option B: Teflon** - Similar to polythene, Teflon (polytetrafluoroethylene) is also produced via addition polymerization.
- **Option C: Phenol Formaldehyde** - This is a type of condensation polymer, formed by the reaction of phenol and formaldehyde, resulting in the elimination of water.
- **Option D: Nitrile Rubber** - This is also formed through addition polymerization, specifically from the copolymerization of 1,3-butadiene and acrylonitrile.

3. **Conclusion**:
- From the analysis, **Phenol Formaldehyde (Option C)** is the polymer obtained by condensation polymerization.

### Final Answer:
The polymer obtained by condensation polymerization is **Phenol Formaldehyde (Option C)**.