Limiting factors refers to the factors that limit the size of population. Such factors can be density –dependent or density independent.
Logistic growth curve is seen, when the exponential growth phase, organism’s growth slows down due to limited resources.
Population growth can become constant only, when birth rate equals the death rate after demographic transition.
Carrying capacity is the highest number of organisms that an environment can support.
Exponential growth occurs, when the growth of the population is constant, at a particular rate. But, it varies when the available resources are more than the needs of the population. Population density refers to the number of individuals per unit area.
Hence, the correct option is (d) exponential growth.