Natural rubber is a polymer of

Options

A. cis isoprene
B. trans-isoprene
C. Both (1) and (2)
D. None of the above

Answer

### Step-by-Step Solution:

1. **Understanding Polymers**:
- A polymer is a large molecule made up of repeating structural units called monomers.

2. **Identifying the Monomer of Natural Rubber**:
- Natural rubber is specifically a type of polymer that is derived from a particular monomer.

3. **Recognizing the Monomer**:
- The monomer unit for natural rubber is known as isoprene.
- Isoprene is chemically identified as 2-methyl-1,3-butadiene.

4. **Formation of Natural Rubber**:
- Natural rubber is formed through the process of addition polymerization of isoprene.
- This process involves the linking of multiple isoprene units to create a long-chain polymer.

5. **Source of Natural Rubber**:
- Natural rubber is obtained from the latex of tropical rubber trees, which is a milky white fluid.

6. **Conclusion**:
- Therefore, the correct answer to the question "Natural rubber is a polymer of" is isoprene (2-methyl-1,3-butadiene).

### Final Answer:
Natural rubber is a polymer of isoprene (2-methyl-1,3-butadiene).

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