One of the oldest uses of earthworm is as:-

Options

A. Bait for catching fish
B. Source of manure
C. Food for poultry
D. Medicine for gout

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks about one of the oldest uses of earthworms.

2. **Understand the Context**: Earthworms have been utilized by humans for various purposes throughout history. Recognizing these uses is essential to answering the question correctly.

3. **Consider the Options**: The main focus here is on the traditional uses of earthworms. One prominent use is as bait for fishing.

4. **Define Bait**: Bait is defined as food placed on a hook, in a net, or in a trap to attract fish or other animals. Earthworms serve this purpose effectively due to their natural presence in aquatic environments.

5. **Conclude the Answer**: Given the historical context and the definition of bait, we can conclude that one of the oldest uses of earthworms is as bait for catching fish.

6. **Final Answer**: The correct answer is that earthworms are used as bait for catching fish.

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