Ecology at the level is essentially physio- logical ecology which tries to understand how different organisms are adapted to their environments.

Options

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

Answer

To solve the question, we need to identify the level of ecology that focuses on how individual organisms adapt to their environments. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Levels of Ecology
Ecology can be studied at different levels: organism, population, community, and ecosystem. Each level focuses on different aspects of interactions and adaptations.

### Step 2: Define Physiological Ecology
Physiological ecology is a branch of ecology that examines how organisms' physiological traits help them adapt to their environments. This includes adaptations for survival and reproduction.

### Step 3: Identify the Relevant Level
The question specifies "ecology at the organism level," which aligns with physiological ecology. This level focuses on individual organisms and their adaptations to environmental conditions.

### Step 4: Analyze the Options
- **Population**: This level studies groups of individuals of the same species and their interactions.
- **Community**: This level looks at different species living together and their interactions.
- **Ecosystem**: This level encompasses both biotic (living) and abiotic (non-living) components of an environment.
- **Organism**: This level focuses on individual organisms and their adaptations.

### Step 5: Select the Correct Answer
Since the question is about understanding how different organisms adapt to their environments at the individual level, the correct answer is **organism**.

### Final Answer
The correct answer is **organism**.

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