Ecological niche is

Options

A. the surface area of the ocean
B. an ecologically adapted zone
C. the physical position and functional role of a species within the community
D. formed of all plants and animals living at the bottom of a lake

Explanation

### Step-by-Step Solution:

1. **Definition of Ecological Niche**: An ecological niche refers to the role or function of a species within its ecosystem, including its habitat, resource use, and interactions with other organisms.

2. **Ecologically Adapted Zone**: The ecological niche can be described as an ecologically adapted zone. This means that it is a specific area within a habitat where a species is best suited to live and thrive.

3. **Specific Place in Habitat**: The ecological niche is essentially the specific place or position that a species occupies within its habitat. This includes not just the physical location but also the conditions that support the species.

4. **Factors Determining Niche**: The ecological niche is determined by various factors, including the range of tolerance of the species. This range refers to the environmental conditions (like temperature, humidity, etc.) that a species can withstand.

5. **Functional Role**: The ecological niche also encompasses the functional role of the species within the community. This includes how the species interacts with other organisms, such as its role in the food web, its reproductive strategies, and its behavior.

6. **Conclusion**: Therefore, the most appropriate definition of an ecological niche is that it represents the physical position and functional role of a species within a community.

7. **Correct Answer**: Based on the options provided, the correct answer is: "the physical position and functional role of a species within the community."