The function of exodermis in the roots is

Options

A. Prevents exit of water and helps in sec.growth.
B. Prevention of exit of water and protection
C. Prevention of exit of water and allowing entry of water
D. Storage of water and ford materials

Answer

### Step-by-Step Solution:

1. **Understanding Exodermis**: The exodermis is a layer of cells found in the roots of plants, specifically located just beneath the epidermis (the outermost layer). It is typically a single layer of cells.

2. **Function of Exodermis**: The primary function of the exodermis is to act as a barrier. It helps in regulating the movement of water and solutes in and out of the root.

3. **Prevention of Water Loss**: One of the key roles of the exodermis is to prevent the loss of water from the root system. This is crucial for maintaining the plant's hydration and overall health.

4. **Protection Against Pathogens**: The exodermis also serves a protective function by acting as a barrier against pathogens and harmful substances that could invade the root.

5. **Elimination of Incorrect Options**:
- The exodermis does not help in secondary growth, so any option suggesting that is incorrect.
- It does not prevent the entry of water; rather, it regulates it, so options suggesting this are also incorrect.
- The exodermis does not store water or food materials, which eliminates options that state this function.

6. **Conclusion**: Therefore, the correct function of the exodermis in the roots is to prevent the exit of water and provide protection against pathogens.

### Final Answer:
The function of the exodermis in the roots is to prevent the exit of water and provide protection.