Assertion : Productivity generally increases from polar regions towards the tropics .
Reason : It is due to increasing sunlight and temperature towards the tropics .

Options

A. If both Assertion and Reason are true and the Reason is the correct explanation for the Assertion.
B. If both Assertion and Reason are true and the Reason is not the corret explanation of the Assertion .
C. If Assertion is ture the Reason is false .
D. If both Assertion and Reason are false .

Answer

**Step-by-Step Solution:**

1. **Understanding the Assertion**: The assertion states that productivity generally increases from polar regions towards the tropics. This means that as we move from the colder polar regions to the warmer tropical regions, the amount of biological productivity (the rate at which plants and other photosynthetic organisms produce organic compounds) tends to increase.

2. **Understanding the Reason**: The reason provided is that this increase in productivity is due to increasing sunlight and temperature towards the tropics. In tropical regions, there is more sunlight available throughout the year, and temperatures are generally higher and more stable compared to polar regions.

3. **Comparing Conditions in Polar and Tropical Regions**:
- **Temperature**: Tropical regions have relatively constant and warm temperatures, while polar regions experience extreme seasonal variations with long, harsh winters.
- **Sunlight**: Tropical regions receive more sunlight throughout the year, whereas polar regions receive minimal sunlight, especially during winter months.
- **Rainfall**: Tropical regions have high rainfall, which supports diverse vegetation, while polar regions have very low rainfall.

4. **Impact on Productivity**: The favorable conditions in tropical regions (higher temperatures, more sunlight, and adequate rainfall) support greater biodiversity and higher productivity. In contrast, the harsh conditions in polar regions limit vegetation and species diversity, leading to lower productivity.

5. **Conclusion**: Both the assertion and the reason are correct. The assertion correctly states that productivity increases from polar regions to the tropics, and the reason correctly explains that this is due to increased sunlight and temperature in the tropics.

6. **Final Answer**: Therefore, the correct option is that both the assertion and reason are true, and the reason is a correct explanation of the assertion.

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