A deep seated, vascular structure that represents stem

Options

A. spine
B. thorn
C. prickle
D. branch

Answer

To answer the question regarding a deep-seated vascular structure that represents a stem, we can break down the solution into the following steps:

### Step-by-Step Solution

1. **Understanding the Terminology**:
- Begin by defining key terms: "vascular structure" refers to plant structures that contain vascular tissue (xylem and phloem) responsible for the transport of water, nutrients, and food.
- "Deep-seated" indicates that the structure is located internally rather than on the surface.

2. **Identifying Types of Structures**:
- Differentiate between endogenous and exogenous structures.
- Endogenous structures arise from internal tissues (like the endodermis or pericycle), while exogenous structures arise from external tissues (like the epidermis).

3. **Analyzing the Options**:
- Consider the options provided in the context of the question.
- Recognize that thorns are modified stems and are extensions of the inner cortex.

4. **Conclusion**:
- Since thorns are derived from the stem and are vascular in nature, they fit the description of a "deep-seated, vascular structure that represents a stem."
- Therefore, the answer to the question is **thorn**.

### Final Answer
The deep-seated vascular structure that represents a stem is a **thorn**.