Root hairs are the

Options

A. Multicellular elongations of epidermal cells
B. Acellular elongations of epidermal cells
C. Unicellular elongations of epidermal cells
D. Multicellular elongations of endodermal cells.

Answer

### Step-by-Step Solution:

1. **Understanding Root Hairs**:
- Root hairs are specialized structures found on the roots of plants. They play a crucial role in the plant's ability to absorb water and nutrients from the soil.

2. **Identifying the Origin of Root Hairs**:
- Root hairs are extensions of the epidermal cells of the root. The epidermis is the outermost layer of cells that protects the plant and aids in absorption.

3. **Defining the Structure of Root Hairs**:
- Root hairs are described as tubular outgrowths. These outgrowths are specifically known as trichoblasts, which are the hair-forming cells located on the epidermis.

4. **Characterizing Root Hairs**:
- Root hairs are unicellular, meaning they consist of a single cell. They are not multicellular structures. This unicellular nature allows them to efficiently increase the surface area for absorption.

5. **Location of Root Hairs**:
- Root hairs are primarily found in the region of maturation of the root. This is where the cells have elongated and differentiated, allowing for effective nutrient and water uptake.

6. **Conclusion**:
- Based on the above points, root hairs are best described as unicellular elongations of the epidermal cells.

### Final Answer:
Root hairs are the **unicellular elongations of the epidermal cells**.

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