The scientific view is that the increase in global temperature should not exceed 2°C above pre-industrial level. If the global temperature increases beyond 3 °C above the pre-industrial level, what can be its possible impact/impacts on the world? 1. Terrestrial biosphere tends toward a net carbon source. 2. Widespread coral mortality will occur. 3. All the global wetlands will permanently disappear. 4. Cultivation of cereals will not be possible anywhere in the world. Select the correct answer using the code given below.

The question explores the possible impacts of a global temperature increase beyond 3°C above the pre-industrial level. 1. Statement 1 is plausible. Increased temperatures can accelerate decomposition and plant respiration rates. Beyond a certain threshold, these processes might release more carbon than is absorbed through photosynthesis, potentially causing the terrestrial biosphere to shift towards becoming a net carbon source. 2. Statement 2 is highly likely. Coral reefs are extremely sensitive to temperature increases and ocean acidification, both consequences of higher CO2 levels and warming. A 3°C increase would very likely cause severe bleaching events and widespread coral mortality across the world. 3. Statement 3 is an extreme generalization and thus incorrect. While climate change will significantly impact global wetlands (through changes in precipitation, evaporation, sea-level rise, etc.), it is highly unlikely that *all* wetlands would *permanently disappear*. Some may shrink, some may shift, and some coastal ones might be inundated. 4. Statement 4 is also an extreme overstatement and incorrect. A 3°C increase would drastically affect agriculture, shifting growing zones and potentially reducing yields significantly in many areas. However, claiming that cultivation of cereals would not be possible anywhere in the world is inaccurate. Adaptation strategies and regional variations would likely allow cultivation in some places, albeit under different conditions. Therefore, the most scientifically plausible impacts listed are 1 and 2.