Which of the following would be considered an ecosystem?

• A. All the frogs in a wetland
• B. A group of oak trees in a forest
• C. A single species of fish living in a tank
• D. A pond containing fish, plants, water, and microorganisms interacting with their environment

Answer: (D)

Verified step by step guidance

1. Understand the definition of an ecosystem: An ecosystem is a community of living organisms (plants, animals, and microorganisms) interacting with each other and their non-living environment (such as water, air, and soil). Both biotic (living) and abiotic (non-living) components must be present and interacting.
2. Analyze the options provided: Each option represents a different biological grouping or environment. Determine whether each option includes both biotic and abiotic components interacting.
3. Option 1: 'All the frogs in a wetland' - This represents a population of frogs, which is a biotic component. However, it does not explicitly include abiotic components or interactions with other organisms, so it is not an ecosystem.
4. Option 2: 'A group of oak trees in a forest' - This represents a group of trees, which is a biotic component. While it may imply interactions with the environment, it does not explicitly include abiotic components or other organisms, so it is not an ecosystem.
5. Option 3: 'A pond containing fish, plants, water, and microorganisms interacting with their environment' - This includes both biotic components (fish, plants, microorganisms) and abiotic components (water). It also specifies interactions between these components, which is the defining characteristic of an ecosystem. Therefore, this is the correct answer.