When xylem and phloem are arranged in an alternate manner on separate radii, such a vascular bundle is called -

Options

A. Radial
B. Bicollateral
C. Concentric
D. Conjoint

Answer

To solve the question regarding the arrangement of xylem and phloem in vascular bundles, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Vascular Bundles**: Vascular bundles are the strands of vascular tissue in plants, consisting of xylem and phloem. They are responsible for the transport of water, nutrients, and food.

2. **Arrangement of Xylem and Phloem**: The arrangement of xylem and phloem can vary. In this specific case, we need to focus on how they are arranged in relation to each other.

3. **Identifying the Arrangement**: The question specifies that xylem and phloem are arranged in an alternate manner on separate radii. This means that if you were to look at a cross-section of the plant, you would see xylem and phloem positioned on different radii, rather than being adjacent to each other.

4. **Defining the Type of Vascular Bundle**: When xylem and phloem are arranged alternately on separate radii, this configuration is known as a **radial vascular bundle**.

5. **Conclusion**: Therefore, the answer to the question is that when xylem and phloem are arranged in an alternate manner on separate radii, such a vascular bundle is called a **radial vascular bundle**.