Which bryophyte was used as a surgical dressing during World war I?

Options

A. Sargassum
B. Funaria
C. Sphagnum
D. Porella

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks which bryophyte was used as a surgical dressing during World War I.

2. **Recall Relevant Information**: During World War I, certain natural materials were utilized for medical purposes. One of these materials was a type of bryophyte known for its antiseptic properties.

3. **Identify the Bryophyte**: The bryophyte that fits this description is Sphagnum. Sphagnum moss is known for its ability to absorb moisture and its antiseptic qualities due to the presence of iodine.

4. **Explain the Use**: Sphagnum was used as a surgical dressing because it helps keep wounds sterile, preventing infection. Its high iodine content contributes to its antiseptic properties, making it effective for wound care.

5. **Differentiate from Other Bryophytes**: Other bryophytes mentioned include:
- **Sargassum**: Used for cosmetic purposes and paper making.
- **Funaria**: Used for soil fixation.
- **Porrella**: Used for medicinal purposes but not specifically for surgical dressing.

6. **Conclude the Answer**: Based on the information gathered, the correct answer to the question is Sphagnum.

**Final Answer**: Sphagnum

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