Match the Column I with Column II :

A-3,B-4,C-1,D-2

The correct answer is Option (2) -A-3,B-4,C-1,D-2

A. Natural ecosystem -3. Forest:

A natural ecosystem is a community of living organisms and their environment that functions as a self-sustaining system. Forests are an example of natural ecosystems, where plants, animals, and microorganisms interact with their physical environment.

B. Decomposer -4. Bacteria:

Decomposers are organisms that break down dead organic material, returning essential nutrients to the ecosystem. Bacteria are common decomposers that play a critical role in the decomposition process by breaking down complex organic compounds into simpler substances.

C. Primary productivity -1. Producer:

Primary productivity refers to the rate at which producers, like plants and algae, convert sunlight into chemical energy through photosynthesis. Producers form the base of the food chain and are responsible for primary productivity in an ecosystem.

D. Secondary productivity - 2. Consumer:

Secondary productivity is the generation of biomass by consumers, organisms that obtain energy by eating other organisms. Consumers are typically herbivores, carnivores, or omnivores that rely on producers or other consumers for their energy needs.