Natural polymer out of the following is

Options

A. Oils
B. Protein
C. Buna-S
D. Polythene

Explanation

To determine the natural polymer from the given options, let's analyze each option step by step.

### Step 1: Identify the Options
The options provided are:
1. Oils
2. Proteins
3. Buoniase
4. Buonane

### Step 2: Classify Each Option
- **Oils**: Oils are generally not classified as polymers. They are lipids and consist of fatty acids and glycerol but do not form long chains of repeating units like polymers do.

- **Proteins**: Proteins are indeed natural polymers. They are made up of long chains of amino acids, which are the monomeric units of proteins.

- **Buoniase**: This appears to be a synthetic polymer. It does not occur naturally and is manufactured through chemical processes.

- **Buonane**: Similar to Buoniase, this is also a synthetic polymer and does not occur naturally.

### Step 3: Conclusion
From the analysis, the only natural polymer among the options is **Proteins**.

### Step 4: Explanation of Proteins as Natural Polymers
Proteins are formed by the polymerization of amino acids. The monomeric units (amino acids) join together through peptide bonds, forming a long chain, which is characteristic of polymers.

For example, the reaction between glycine (NH2CH2COOH) and alanine (NH2CH(CH3)COOH) can be represented as follows:

1. Glycine: NH2-CH2-COOH
2. Alanine: NH2-CH(CH3)-COOH

When these two amino acids react, they form a dipeptide through the elimination of a water molecule (condensation reaction):

\[ \text{Glycine} + \text{Alanine} \rightarrow \text{Glycylalanine} + \text{H}_2\text{O} \]

The resulting structure contains an amide linkage (also known as a peptide bond), which is characteristic of proteins.

### Final Answer
The natural polymer out of the given options is **Proteins**.

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