Usnic acid is an antibiotic obtained from

Options

A. Fungi
B. Bacteria
C. Lichens
D. Algae

Answer

**Step-by-step solution:**

1. **Understanding Usnic Acid**: Usnic acid is a compound that has antibiotic properties. It is important to identify its source to understand its application in medicine.

2. **Identifying Sources of Antibiotics**: Antibiotics are typically derived from natural sources such as fungi, bacteria, lichens, and algae. Each of these organisms produces various compounds that can inhibit the growth of bacteria or fungi.

3. **Narrowing Down the Options**: The question provides four options: fungi, bacteria, lichens, and algae. We need to determine which of these is the source of usnic acid.

4. **Research on Usnic Acid**: Upon researching, it is established that usnic acid is specifically derived from lichens. Lichens are symbiotic associations between fungi and algae or cyanobacteria, and they produce various metabolites, including usnic acid.

5. **Conclusion**: Therefore, usnic acid is an antibiotic obtained from lichens.

**Final Answer**: Usnic acid is an antibiotic obtained from lichens.

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