<em>The correct option is b) exponential growth curve</em>
Explanation:
A J-shaped curve can be described as a curve on a graph which represents the phase of exponential growth. During this phase, the population of a certain organism expands rapidly in an exponential manner unless it is stopped due to some factor such as environmental resistance. A J-shaped curve will usually be seen in a new environment when the number of resources is more in the environment to support the growth of the population.
Because since developing countries are still growing, when they finally get to the level of some more advanced countries the country as a whole feels a "greater growth"
