The growth of the pollen tube towards the ovules is known as

Options

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

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the specific term that describes the growth of the pollen tube towards the ovule.

2. **Analyzing the Options**:
- **Option 1: Phototropism**: This refers to the growth of plants in response to light. Since the question is about the pollen tube's growth towards the ovule, this option is not applicable.

- **Option 2: Chemotropism**: This term describes the growth of an organism in response to chemicals. In the case of pollen tubes, they grow towards the ovule due to chemical signals released by the ovule. This option is likely the correct answer.

- **Option 3: Geotropism**: This involves the growth of plant parts in response to gravity. For example, roots grow downwards due to gravity. This option does not relate to the pollen tube's growth.

- **Option 4: Hydrotropism**: This refers to the growth of plant parts in response to water. Again, this does not pertain to the growth of the pollen tube towards the ovule.

3. **Conclusion**: After analyzing all the options, the correct answer is **Chemotropism**, as it accurately describes the growth of the pollen tube towards the ovule in response to chemical signals.

**Final Answer**: The growth of the pollen tube towards the ovules is known as **Chemotropism**.

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