Structurally a biodegradable detergent should contain a

Options

A. normal alkyl chain
B. branched alkyl chain
C. phenyl side chain
D. cyclohexyl side chain

Explanation

### Step-by-Step Solution:

1. **Understanding Biodegradable Detergents**:
- Biodegradable detergents are designed to break down naturally in the environment without causing harm. This means they should degrade quickly after being used.

2. **Structure of Detergents**:
- Detergents can be classified based on their molecular structure. They can have branched or linear structures.

3. **Branched vs. Linear Structures**:
- Branched detergents tend to be non-biodegradable because their complex structure makes it difficult for microorganisms to break them down.
- Linear detergents, on the other hand, have a simpler structure that allows for easier degradation by microorganisms.

4. **Components of Linear Detergents**:
- Linear biodegradable detergents typically contain a normal alkyl chain. This is a straight-chain hydrocarbon that is more easily broken down by natural processes.

5. **Example of a Biodegradable Detergent**:
- An example of a biodegradable detergent is Sodium Alkyl Benzene Sulphonate, which contains a normal alkyl chain that can be easily degraded.

6. **Conclusion**:
- Therefore, structurally, a biodegradable detergent should contain a **normal alkyl chain**.

### Final Answer:
A biodegradable detergent should contain a **normal alkyl chain**.

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