Many parasites have evolved to be $A$ in such a way that both host and the parasite tend to $B$; that is,if the host evolves special mechanisms for rejecting or resisting the parasite,the parasite has to evolve mechanisms to $C$ and neutralize them,in order to be successful with the same host species.
Choose the correct option for $A$,$B$,and $C$.

The association between a suckerfish $(Remora)$ and a shark is an example of:

The most successful parasite is one that:

In a stable population,what is the ecological role of predation?

Which of the following statements regarding species interdependence are true?
$I.$ An association of two species where one is benefited and the other remains unaffected is called mutualism.
$II.$ An interspecific association where both partners derive benefit from each other is called commensalism.
$III.$ $A$ direct food relation between two species of animals in which one animal kills and feeds on another is referred to as predation.
$IV.$ $A$ relationship between two species of organisms where both partners are benefited from each other is called symbiosis.

What did Gause demonstrate regarding ecology and competition?