Vascular bundle having phloem at the centre encircled by xylem is know as

Options

A. bicollateral
B. conjoint collateral
C. amphivasal
D. amphicribral

Answer

To solve the question regarding the type of vascular bundle having phloem at the center encircled by xylem, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Vascular Bundles**: Vascular bundles are structures in plants that contain xylem and phloem, which are responsible for the transport of water, nutrients, and food.

2. **Identify Types of Vascular Bundles**: There are several types of vascular bundles based on the arrangement of xylem and phloem:
- **Bicollateral**: Xylem is in the center, with phloem on both sides.
- **Conjoined Collateral**: Xylem and phloem are on the same radius, with xylem inside and phloem outside.
- **Amphivessel**: Phloem is at the center, surrounded by xylem.
- **Amphicribral**: Xylem is in the center, surrounded by phloem.

3. **Analyze the Question**: The question specifically asks for a vascular bundle where phloem is at the center and encircled by xylem.

4. **Match with Definitions**: From the definitions:
- The **amphivessel** type matches the description provided in the question, as it has phloem in the center surrounded by xylem.

5. **Conclusion**: Therefore, the correct answer to the question is **amphivessel**.

### Final Answer:
The vascular bundle having phloem at the center encircled by xylem is known as **amphivessel**.

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