Natural rubber is basically of or the
monomer of natural polymer rubber is

Options

A. Neoprene
B. Isoprene
C. Chloroprene
D. Butadiene

Explanation

### Step-by-Step Solution:

1. **Understanding Natural Rubber**:
- Natural rubber is a polymer that is derived from natural sources. It is primarily obtained from the latex of rubber trees.

2. **Identifying the Monomer**:
- The monomer of natural rubber is isoprene. A monomer is the basic building block that links together to form a polymer.

3. **Structure of Isoprene**:
- The chemical structure of isoprene can be represented as:
- H2C=C(CH3)-CH=CH2
- This shows that isoprene has a double bond and consists of five carbon atoms.

4. **Conclusion**:
- Therefore, the answer to the question is that the monomer of natural rubber is isoprene.

### Final Answer:
The monomer of natural polymer rubber (natural rubber) is isoprene.

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