Negative phototropism occurs in

Options

A. Root
B. Stem
C. Leaf
D. Flower.

Answer

### Step-by-Step Solution:

1. **Understand Phototropism**: Phototropism is the growth or movement of a plant in response to light. It can be classified into two types: positive phototropism and negative phototropism.

2. **Define Positive and Negative Phototropism**:
- **Positive Phototropism**: This occurs when plant parts grow towards the light. Examples include the tips of stems and leaves.
- **Negative Phototropism**: This occurs when plant parts grow away from the light.

3. **Identify the Examples**:
- Positive phototropism is exhibited by stems and leaves, which bend towards the light due to the action of auxins.
- Negative phototropism is exhibited by roots, which bend away from the light.

4. **Analyze the Options**:
- **Option 1: Root** - Correct, as roots exhibit negative phototropism.
- **Option 2: Stem** - Incorrect, as stems exhibit positive phototropism.
- **Option 3: Leaf** - Incorrect, as leaves also exhibit positive phototropism.
- **Option 4: Flower** - Incorrect, as flowers generally grow towards light, indicating positive phototropism.

5. **Conclusion**: The correct answer to the question "Negative phototropism occurs in" is **Option 1: Root**.