Natural indicator litmus is extracted from:

Options

A. Lichens
B. Earthworm
C. Ant
D. Algae

Answer

To answer the question about the natural indicator litmus and its source, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Natural Indicators**:
- Natural indicators are substances that change color in response to changes in pH (acidity or basicity) of a solution. They are derived from natural sources, unlike synthetic indicators.

2. **Identifying Litmus**:
- Litmus is a well-known natural indicator that is commonly used in chemistry to determine whether a solution is acidic or basic.

3. **Source of Litmus**:
- Litmus is extracted from lichens, which are symbiotic organisms made up of fungi and algae or cyanobacteria. The specific type of lichen used for extracting litmus is usually from the genus *Roccella*.

4. **Conclusion**:
- Therefore, the answer to the question "Natural indicator litmus is extracted from:" is "lichens".

### Final Answer:
Natural indicator litmus is extracted from lichens.

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