Which model is considered a more realistic one?

Any species growing $A$ under unlimited resource conditions can reach enormous population densities in a short time. Darwin showed how even $B$ growing animal like elephant could reach enormous numbers in absence of check and that characteristics of organism is called $C$. Choose the correct option for $A, B$ or $C$ respectively.

The population growth curves are given below. Identify the equations for $P$ and $Q$.

Verhulst-Pearl logistic growth shows . . . . . . curve.

In a population,the number of pre-reproductive age organisms is more than the post-reproductive age organisms. As a result,the population will .....

Under which of the following conditions is the logistic population growth curve obtained?