Which of the following causes almost unbearable irritation of the skin?

Options

A. (a) lint of Gossypium
B. (b) staminal hair of Tradescantia
C. (c) prickles of Rosa indica
D. (d) stinging hair of Urtica dioica

Explanation

**Step-by-Step Solution:**

1. **Identify the Options**: The question provides four options that could potentially cause skin irritation:
- A) Lint of Gossypium
- B) Staminal hair of Tradescantia
- C) Prickles of Rosa Indica
- D) Stinging hair of Urtica dioica

2. **Understand the Structure of Trichomes**: Trichomes are hair-like structures found on the surfaces of plants, including leaves and stems. They can serve various functions, including protection and secretion of substances.

3. **Analyze Each Option**:
- **Gossypium (Cotton)**: The lint from cotton is generally soft and does not cause irritation.
- **Tradescantia**: Staminal hairs may not be known for causing significant irritation.
- **Rosa Indica (Rose)**: Prickles can cause minor injuries but are not typically associated with unbearable irritation.
- **Urtica dioica (Nettle)**: Known for its stinging hairs, which are specifically designed to cause irritation.

4. **Focus on Urtica dioica**: The stinging hairs (trichomes) of Urtica dioica are filled with irritants. When these hairs come into contact with skin, they break and release these irritants, leading to a painful and irritating reaction.

5. **Conclusion**: Based on the analysis, the option that causes almost unbearable irritation of the skin is:
- **D) Stinging hair of Urtica dioica**.

6. **Final Statement**: Hence, the correct answer is option D, stinging hair of Urtica dioica.

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