Ecological terms like niche and habitat form the foundation of environmental biology for NEET and competitive exams. This guide solves a key matching question with the correct answer and breaks down all options.

Correct Answer

The correct matching is (B) P-ii, Q-iv, R-i, S-iii. Niche aligns with the organism’s role in its biotic environment including food and enemies, biota with the total organisms in a region, trophic level with food chain position, and habitat with physical environment.​

Term Definitions

• P. Niche (ii): Describes an organism’s functional role, its relations to food resources, competitors, predators, and enemies in the biotic environment.​

• Q. Biotas (iv): Refers to the complete set of flora and fauna, or all living organisms, in a specific place or region.​

• R. Trophic level (i): Indicates a species’ position in the food chain, such as producer, primary consumer, or top predator.​

• S. Habitat (iii): The physical living space or address of an organism, including abiotic factors like soil, water, and climate.​

Option Analysis

Option (A) P-i, Q-ii, R-iv, S-iii mismatches niche with food chain position, which is trophic level, and confuses biota.​
Option (B) P-ii, Q-iv, R-i, S-iii correctly pairs each term with its standard definition in ecology.​
Option (C) P-iv, Q-iii, R-i, S-ii wrongly assigns niche to totality of organisms and habitat to biotic relations.​
Option (D) P-iii, Q-i, R-ii, S-iv inverts habitat and niche while misplacing others.​