Sporangiophores of Equisetum are

Options

A. Peltate
B. Whorled
C. Stalked
D. All the above.

Answer

To answer the question about the sporangiophores of Equisetum, we will break down the information step by step.

### Step-by-Step Solution:

1. **Understanding Equisetum**:
- Equisetum, commonly known as horsetail, belongs to the group of plants called pteridophytes.
- Pteridophytes are vascular plants that reproduce via spores instead of seeds.

**Hint**: Remember that Equisetum is a type of pteridophyte, which is crucial for understanding its reproductive structures.

2. **Identifying Sporangiophores**:
- Sporangiophores are specialized structures that produce spores in Equisetum.
- They are found at the tips of the aerial shoots of the plant.

**Hint**: Focus on the role of sporangiophores in the reproduction of Equisetum.

3. **Structure of Sporangiophores**:
- Each cone at the tip of the shoot has a central axis, which is the stalk of the sporangiophore.
- The central axis bears whorls of peltate appendages, which are the sporangiophores.

**Hint**: Visualizing the structure can help; think of the cone shape with a central stalk and appendages around it.

4. **Characteristics of Sporangiophores**:
- The sporangiophores are described as peltate (disc-like), whorled (arranged in circles), and stalked (attached to the central axis).
- Each disc can have around 10 to 15 sporangiophores that produce spores.

**Hint**: Remember the three characteristics: peltate, whorled, and stalked, as they are key to answering the question.

5. **Conclusion**:
- Since sporangiophores of Equisetum exhibit all the mentioned characteristics (peltate, whorled, and stalked), the correct answer to the question is "all of the above."

**Hint**: When faced with multiple characteristics in a question, check if the subject meets all the criteria listed in the options.

### Final Answer:
The sporangiophores of Equisetum are **all of the above** (peltate, whorled, and stalked).