It is observed that in a field of sunflowers, all the sunflowers face toward Sun. The given phenomenon is an example of

Options

A. gravitropisin
B. phototropism
C. hydrotropism
D. thignotropism

Answer

**Step-by-Step Solution:**

1. **Understanding the Phenomenon**: The question describes a situation where all sunflowers in a field are observed to face towards the Sun. This behavior indicates a specific response of the plants to their environment.

2. **Identifying the Options**: The options provided are Gravitropism, Phototropism, Hydrotropism, and Thigmotropism. We need to analyze these terms to find out which one correctly describes the phenomenon of sunflowers facing the Sun.

3. **Analyzing Gravitropism**: Gravitropism refers to the growth of plant roots in response to gravity. Roots grow downward due to positive gravitropism, while some plants may exhibit negative gravitropism by growing upward. Since this phenomenon is related to gravity, it does not apply to the sunflowers facing the Sun.

4. **Analyzing Phototropism**: Phototropism is the growth or movement of plants in response to light. In this case, the sunflowers are orienting themselves towards the light source, which is the Sun. This behavior is a classic example of phototropism.

5. **Analyzing Hydrotropism**: Hydrotropism refers to the growth of plants in response to moisture or water. This is not relevant to the sunflowers’ orientation towards the Sun.

6. **Analyzing Thigmotropism**: Thigmotropism is the directional growth movement in response to touch. This is seen in plants like climbing vines or tendrils but does not apply to the sunflowers facing the Sun.

7. **Conclusion**: After analyzing all the options, the correct answer to the phenomenon of sunflowers facing the Sun is **Phototropism**.

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