Vascular bundles of are

Options

A. conjoint, collateral and closed
B. conjoint, collaterla or bicollateral and closed
C. conjoint, collateral or bicollateral and open
D. conjoint, bicollateral and open

Answer

### Step-by-Step Solution:

1. **Identify the Type of Plant**: The question is about the vascular bundles in a dicot stem. Dicotyledons (dicots) are a group of flowering plants that typically have two embryonic leaves or cotyledons.

2. **Understand the Structure of Vascular Bundles**: In a dicot stem, vascular bundles are organized in a specific manner. They are arranged in a ring formation, unlike monocots where they are scattered throughout the stem.

3. **Components of Vascular Bundles**: Each vascular bundle in a dicot stem consists of:
- **Phloem**: This is located on the outer side of the vascular bundle and is responsible for the transport of nutrients and food.
- **Cambium**: This is a layer of meristematic tissue that is responsible for the secondary growth of the plant. It is located between the phloem and xylem.
- **Xylem**: This is located on the inner side of the vascular bundle and is responsible for the transport of water and minerals from the roots to the rest of the plant.

4. **Type of Vascular Bundle**: The vascular bundles in dicots are classified as:
- **Conjoint**: This means that the phloem, cambium, and xylem are found together in the same bundle.
- **Bicolateral**: This indicates that both phloem and xylem are present in the same vascular bundle.
- **Open**: This means that the presence of cambium allows for secondary growth, which is characteristic of dicots. In contrast, monocots have closed vascular bundles without cambium.

5. **Conclusion**: Therefore, the vascular bundles in a dicot stem are conjoint, bicolateral, and open.

### Final Answer:
The vascular bundles of a dicot stem are conjoint, bicolateral, and open.

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