The distinguishing feature of open vascular bundles is presence of

Options

A. a) Cambium
B. b) Xylem and phloem
C. c) Pericycle
D. d) Endodermis

Answer

**Step-by-Step Solution:**

1. **Understanding Vascular Bundles**: Vascular bundles are the part of the plant's vascular system that transport water, nutrients, and food. They consist of xylem and phloem.

2. **Types of Vascular Bundles**: There are two main types of vascular bundles: open and closed. The distinction between them is based on the presence or absence of cambium.

3. **Definition of Open Vascular Bundles**: Open vascular bundles contain an interfascicular cambium, which is a layer of meristematic tissue located between the xylem and phloem.

4. **Role of Cambium**: The cambium allows for secondary growth, meaning that the plant can grow thicker over time. In open vascular bundles, the xylem and phloem are not in direct contact because the cambium is present between them.

5. **Closed Vascular Bundles**: In contrast, closed vascular bundles do not have this cambium layer, resulting in the xylem and phloem being in direct contact with each other.

6. **Identifying the Distinguishing Feature**: The key distinguishing feature of open vascular bundles is the presence of cambium. Therefore, when asked about the distinguishing feature of open vascular bundles, the answer is the presence of cambium.

7. **Final Answer**: The correct option is A: cambium.

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