The scientific view is that the increase in global temperature should not exceed $2^{\circ}\mathrm{C}$ above pre-industrial level. If the global temperature increases beyond $3^{\circ}\mathrm{C}$ 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.