Which of the following are the harmful effect of global warming
I.The temperature of the earth has increased by `0.6^@C` in last three decades which will lead to change in precipitation patterns
II.This rise in temperature will lead to the increased melting of polar ice caps which will cause the rise in sea level and many coastal areas will be submerged
III.Increased temperature will lead to increase weed growth eruption of diseases and pests thus crop productivity will decrease

Options

A. I and II
B. I and III
C. II and III
D. all of these

Answer

**Step-by-Step Solution:**

1. **Understanding Global Warming**: Global warming refers to the long-term increase in Earth's average surface temperature due to human activities, primarily the emission of greenhouse gases.

2. **Analyzing Statement I**: The first statement mentions that the Earth's temperature has increased by 0.6°C in the last three decades, which can lead to changes in precipitation patterns. This is true, as rising temperatures can alter weather patterns, affecting rainfall distribution and intensity.

3. **Analyzing Statement II**: The second statement discusses the melting of polar ice caps due to rising temperatures, which leads to a rise in sea levels. This is also accurate, as the melting ice contributes to higher sea levels, which can submerge coastal areas, posing risks to human settlements and ecosystems.

4. **Analyzing Statement III**: The third statement asserts that increased temperatures will promote weed growth, increase the eruption of diseases and pests, and consequently decrease crop productivity. This statement is valid, as warmer temperatures can create favorable conditions for weeds and pests, leading to lower agricultural yields.

5. **Conclusion**: All three statements (I, II, and III) accurately describe harmful effects of global warming. Therefore, they are all correct.

**Final Answer**: All of the above statements (I, II, and III) are harmful effects of global warming.

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