The growth of the roots of plants towards a source of water is known as

Options

A. phototropism
B. geotropism
C. hydrotropism
D. chemotropism

Answer

To solve the question regarding the growth of the roots of plants towards a source of water, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the phenomenon where plant roots grow towards a source of water.

2. **Identifying Key Terms**: The key terms here are "growth of roots" and "towards a source of water."

3. **Reviewing the Options**: The options provided are:
- Photo-tropism
- Geo-tropism
- Hydro-tropism
- Chemo-tropism

4. **Analyzing Each Option**:
- **Photo-tropism**: This refers to the growth of plants towards light. Hence, this option is incorrect for our question.
- **Geo-tropism**: This is the growth of plant parts in response to gravity. Since the question is about water, this option is also incorrect.
- **Hydro-tropism**: This term specifically refers to the growth of plant roots towards moisture or water. This matches the question perfectly.
- **Chemo-tropism**: This refers to the growth of plants in response to chemical stimuli, which is not relevant here.

5. **Conclusion**: Based on the analysis, the correct answer to the question is **Hydro-tropism**.

### Final Answer:
The growth of the roots of plants towards a source of water is known as **Hydro-tropism**.

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