The plant growth is regulated by

Options

A. Climatic factor
B. Growth hormones
C. Both (1) and (2)
D. None of these

Answer

To answer the question "The plant growth is regulated by," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Plant Growth**:
- Plant growth is defined as the increase in size and mass of the plant, which includes both growth and differentiation.

2. **Identify the Factors Influencing Plant Growth**:
- Plant growth is influenced by two types of factors:
- **Intrinsic Factors (Internal)**: These are factors that originate from within the plant itself, primarily involving growth hormones.
- **Extrinsic Factors (External)**: These are environmental factors that affect plant growth, such as climatic conditions (light, temperature, humidity, etc.), nutrition, and oxygen availability.

3. **Recognize the Role of Growth Hormones**:
- Growth hormones (also known as plant hormones) play a crucial role in regulating various aspects of plant growth and development, including cell division, elongation, and differentiation.

4. **Acknowledge the Impact of Climatic Factors**:
- Climatic factors such as light intensity, temperature, and water availability significantly influence the growth rate and overall health of plants.

5. **Conclude the Regulation of Plant Growth**:
- Since both intrinsic factors (growth hormones) and extrinsic factors (climatic conditions) are essential for regulating plant growth, we can conclude that plant growth is regulated by both.

6. **Select the Correct Option**:
- Based on the analysis, the correct answer to the question is "both first and second," meaning plant growth is regulated by both growth hormones and climatic factors.

### Final Answer:
The plant growth is regulated by both growth hormones and climatic factors.

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