Vascular bundles having xylem and phloem on different radii.

Explanation

### Step-by-Step Solution:

1. **Understanding Vascular Bundles**: Vascular bundles are structures found in vascular plants that are responsible for the transport of water, nutrients, and food. They consist of two main types of vascular tissues: xylem and phloem.

2. **Identifying the Types of Vascular Bundles**: Vascular bundles can be categorized based on the arrangement of xylem and phloem. The two primary types are:
- **Radial Vascular Bundles**: Here, xylem and phloem are arranged in separate groups and are located at different radii.
- **Conjoined Vascular Bundles**: In this type, xylem and phloem are located on the same radius but opposite each other.

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