Jointed green stem occurs in

Options

A. Lycopodium
B. Selaginella
C. Equisetum
D. Pteridium.

Answer

To solve the question "Jointed green stem occurs in," we will analyze each option provided and identify which one corresponds to a plant with a jointed green stem.

### Step-by-Step Solution:

1. **Understanding the Term "Jointed Green Stem":**
- A jointed green stem refers to a stem that has nodes and internodes and is capable of photosynthesis due to the presence of chlorophyll.

2. **Analyzing the Options:**
- **Option 1: Lycopodium**
- Lycopodium is a type of club moss. It has a simple stem structure and does not have a jointed green stem. Therefore, this option is incorrect.

- **Option 2: Salazimella**
- Salazimella is a lesser-known plant and does not have a jointed green stem. This option is also incorrect.

- **Option 3: Equisetum**
- Equisetum, commonly known as horsetail, is characterized by its jointed green stems that have nodes and internodes. This plant is capable of photosynthesis through its stem. Therefore, this option is correct.

- **Option 4: Pteridium**
- Pteridium, commonly known as bracken fern, does not have a jointed green stem. This option is incorrect.

3. **Conclusion:**
- After analyzing all the options, we find that the only plant with a jointed green stem is **Equisetum**. Thus, the correct answer is **Option 3: Equisetum**.

### Final Answer:
The jointed green stem occurs in **Equisetum**.

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