Which of the following is not a defence evolved by a prey to avoid predators?

Two closely related species competing for the same resources cannot coexist indefinitely and the competitively inferior will be eliminated eventually. This principle is known as:

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.

Which one of the following is $NOT$ an adaptation found in endoparasites?

Competition for light,nutrients,and space is most severe between:

In the following,which interaction is indicated by $+/-$?