Above given diagram represents a relationship with the environment. This relation is known as:

(a) Species ecology
(b) Autecology
(c) Synecology
(d) Gene ecology

Hint: The study of different species along with their way of interacting with each other or with living organisms, and non-living organisms. They live in a particular area called niche and their interaction is studied in this area.

Complete answer:
The branch of the study of the interaction of various species along with the living and nonliving organisms and matters in their surroundings is known as species ecology. It may sometimes also be called autecology.
The branch of biology which at the level of communities, populations, and ecosystems is dealing with the distribution, abundance, and interaction of living organisms, is known as ecology and has a different subfield.
-The study of the interaction of living and nonliving factors with an individual organism or a single species of its environment is known as autecology.
-It is an experimental method dealing with various variables in order to understand the needs of life history and behavior of the organisms or species. The variables include light, humidity, and available nutrients.
-The distribution, structure, demography, and abundance of organisms that coexist in a community are studied by synecology.
-The distribution and abundance of demography and interaction between the coexisting groups of organisms are encompassed by them.
-Interspecific interactions come under Synecology.
-Gene ecology is the study of the various genes and their expressions in different non-living factors or mediums. It also explains the structure of DNA or RNA of various organisms.

So, the correct answer is ‘Species ecology’.

Note:
In ecology and ecological units comprises a group of organisms or a population of various species that occupies a particular area and interact with one another and their environment.
-It usually focuses on understanding the interaction of a group of organisms within a community.
-It also helps in the study of the symbiotic relationship that occurs in a community like competition, mutualism, commensalism, and predator-prey population dynamics.