Question

Select the correct match

I	II
(i)Competition	(a)Tapeworm and man
(ii)Commensalism	(b)Lichen
(iii)Mutualism	(c)Cattle egret and cattle
(iv)Parasitism	(d)Lions and leopards

(a)i-d,ii-c,iii-b,iv-a
(b)i-d,ii-b,iii-c,iv-a
(c)i-c,ii-b,iii-d,iv-a
(d)i-a,ii-b,iii-d,iv-c

Answer 1

Hint: An ecological community can be defined as a set of actually or potentially interacting species living in the same environment. This community in turn is bonded together by the network of influences that species have on one another.

Complete answer:
Biological interaction means that whatever affects one species also affects many others and helps maintain the "balance of nature". The table below displays the different types of interactions and their effects on species.

Type of interaction	Sign	Effects	Example
Mutualism	+/+	Both species benefit from interaction	Lichen shows mutualistic interaction between fungus and algae.
Competition	-/-	Each species affect negatively	Lions and leopards.
Commensalism	+/0	One species is affected other remains unaffected	Cattle egret and cattle.
Parasitism	+/-	One species benefits and one is disadvantaged	Tapeworm and man.

Lichens are made of two closely interacting organisms namely a fungus, and one or more partners, called photobionts. The photobiont could be an alga or cyanobacteria which can produce food source by photosynthesis. In contrast, the fungal component is 'heterotrophic' and requires an external source of food. The fungi help build the structure for the lichen called thallus, within which they provide a suitable environment for a long term, stable association with their photobionts.

Interspecific competition is a form of competition between individuals of different species that compete for the same resource in an ecosystem (eg: food or living space).Like a dominant male lion chasing a leopard in which both species mostly feed on the same prey. Both can be negatively impacted by the presence of the other as this means they will have less food source.

Egrets remove parasitic ticks from the cattle's body which may feed cattle blood and transmit different diseases. By consuming these ticks the egrets acquire some nutrients from the consumed ticks. Hence they both have shared benefits.
Taeniasis is an infectious disease in humans and is caused by the tapeworm species Taenia saginata (beef tapeworm), Taenia solium (pork tapeworm), and Taenia asiatica (Asian tapeworm). Humans can become infected with these tapeworms by eating raw or undercooked meat products.

Hence, the correct answer is option (A).

Note: Species interactions form the base for many ecosystem properties and processes such as nutrient cycling and food webs. The nature of these interactions can vary among different organisms and depends on the evolutionary context and environmental conditions in which they occur.