The scientific view is that the world temperature should not rise by more than 2 degrees C above pre-industrial levels. If the world temperature rises by more than 3 degree C above pre-industrial level, what will be its possible impact on the world? 1. Terrestrial biosphere will tend towards a net carbon source. 2. Widespread coral mortality will occur. 3. All the global wetlands will be permanently extinct. 4. Cultivation of cereals will not be possible anywhere in the world.

• A. only 1
• B. 1 and 2
• C. 2,3 and 4
• D. All of the above