Which of the following fern spreads very fast by means of leaf tip?

Options

A. Pteridium
B. Azolla
C. Adiantum
D. Alsophila

Answer

**Step-by-Step Solution:**

1. **Identify the Question**: The question asks which fern spreads very fast by means of its leaf tip.

2. **List the Options**: The options provided are:
- a) Pteridium
- b) Azolla
- c) Adiantum
- d) Alsopila

3. **Analyze Each Option**:
- **Pteridium**: Known as bracken fern, it does not primarily spread through leaf tips.
- **Azolla**: This is a water fern that reproduces through spores and vegetative means, but not specifically through leaf tips.
- **Adiantum**: Commonly known as the walking fern, it is known for its ability to spread through adventitious buds located at the tips of its leaves.
- **Alsopila**: This fern does not have a notable method of spreading through leaf tips.

4. **Conclude the Answer**: Based on the analysis, the fern that spreads very fast by means of leaf tips is **Adiantum** (specifically **Adiantum cordatum**).

5. **Explain the Mechanism**: Adiantum spreads by having its leaf tips touch the ground, where they can root and give rise to new plants, facilitating rapid spread.

**Final Answer**: The fern that spreads very fast by means of leaf tip is **Adiantum**.

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