Plant roots tend to grow deeper into the soil to absorb more water. This type of behavioral response in plants is called

Options

A. thigmotropism
B. hydrotropism
C. phototropism
D. gravitropism

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the behavioral response of plant roots growing deeper into the soil to absorb more water.

2. **Identifying the Response**: The growth of plant roots towards moisture is a specific type of response. Roots tend to grow in the direction where water is more available.

3. **Defining the Term**: The term that describes the growth of plant roots in response to water is "hydrotropism." The prefix "hydro-" refers to water.

4. **Explaining Hydrotropism**: Hydrotropism is the directional growth of plant roots towards moisture. This adaptation helps plants to maximize their water absorption from the soil.

5. **Conclusion**: Therefore, the behavioral response of plant roots growing deeper into the soil to absorb more water is called "hydrotropism."

**Final Answer**: Hydrotropism

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