Basic unit of ecological hierarchy is

Options

A. population
B. community
C. ecosystem
D. individual

Explanation

**Step-by-Step Solution:**

1. **Understanding Ecological Hierarchy**: The ecological hierarchy is a system used by ecologists to organize the biological world into different levels of organization, ranging from the largest to the smallest.

2. **Levels of Ecological Hierarchy**: The levels of ecological hierarchy, in order from largest to smallest, are:
- **Biosphere**: The global sum of all ecosystems.
- **Biomes**: Large regions characterized by specific climate conditions and types of organisms.
- **Ecosystems**: Communities of living organisms interacting with their physical environment.
- **Community**: A group of different species living together in one area.
- **Population**: A group of individuals of the same species living in a specific area.
- **Individual**: A single organism.

3. **Identifying the Basic Unit**: Among these levels, the most basic unit of ecological hierarchy is the **individual**. This is because all other levels (population, community, ecosystem, and biome) are made up of individuals.

4. **Conclusion**: Therefore, the answer to the question "Basic unit of ecological hierarchy is" is **individual**.

**Final Answer**: The basic unit of ecological hierarchy is the **individual**.

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