The study which involves the inter-relationship between groups of organisms or species of organisms living together in an area is

Step 1: Analyze the question The question asks for the name of the study of relationships between groups or species of organisms living together in an area. The key phrases are "study", "groups of organisms" and "living together".

Step 2: Explain the concepts Ecology can be studied at two levels:

• Autecology is the study of a single species and its relationship with its environment. "Auto" means self.
• Synecology is the study of communities or groups of different species living together and how they interact with each other and with their environment. "Syn" means together.

Step 3: Check each option

• A. Autecology: This deals with one species only, so it is wrong.
• B. Ecological niche: This is the role or functional position of an organism in its habitat (what it eats, where it lives, how it behaves). It is not a type of study, so it is wrong.
• C. Synecology: This studies groups of organisms or species living together in an area, so it is correct.
• D. Ecosphere: This is the part of the Earth where life exists (the biosphere together with its environment). It is not a type of study, so it is wrong.

Step 4: Answer The correct option is C. Synecology.

Tip: Remember "Syn = Same place, many species" (together), and "Auto = Alone, one species." Prefixes often give away the answer in biology terms.