In an ecosystem when an organism lives together interdependently on biotic factors or other organisms is called an ecological relationship. It can be a favourable or negative relationship.
Mutualism is the relationship between lichen - cyanobacteria and the fungi.
Classification of Ecological association:
- Commensalism is a type of optimistic relationship in which one organism gets profited from another through modes of food, shelter, locomotion etc. Example orchids growing on other trees.
- Predation is an ecological relation in which the predator chases and kills the target for food. For example, snakes hunting mice and rabbits.
- In an ecosystem, two diverse species contest for the same elements is called competition. For example tigers and lions hunting for deer.
- Parasitism is an unfavourable biological relation in which one species profits from the hosts by harming them in certain ways. For example, ticks living on cats and dog fur.
- Mutualism is a positive relationship in which both species benefits from each other by working together. For example, cyanobacteria produce food through biochemical processes and share it with fungi and in return, the fungus provides them with a place to live.
Thus, option E. mutualism is the relation exhibited by lichen cyanobacteria and the fungi.
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