Niche overlap indicates

Options

A. mutualism between two species
B. active cooperation between two species
C. two different parasites on the same host
D. sharing of one or more resources between the two species

Explanation

### Step-by-Step Solution:

1. **Understanding Ecological Niche**:
- The ecological niche refers to the total interactions of a species with its environment, including its role in the ecosystem, its habitat, and its interactions with other species.

2. **Factors Influencing Ecological Niche**:
- The ecological niche is influenced by several factors:
- The species itself.
- Structural adaptations of the species.
- Physical responses of the species to the environment.
- Behavioral traits of the species.

3. **Defining Niche Overlap**:
- Niche overlap occurs when two or more species share one or more resources in their environment. This can include food, space, or other ecological factors.

4. **Analyzing Options**:
- Given the options:
1. Mutualism between two species.
2. Active cooperation between two species.
3. Two different parasite sites on the same host.
4. Sharing one or more resources between the two species.
- We need to determine which option correctly describes niche overlap.

5. **Evaluating Each Option**:
- **Option 1 (Mutualism)**: This describes a relationship where both species benefit, but it does not specifically address resource sharing.
- **Option 2 (Active Cooperation)**: This implies a collaborative relationship, which is not necessarily indicative of niche overlap.
- **Option 3 (Two different parasites on the same host)**: This describes a parasitic relationship, which does not involve resource sharing in the context of niche overlap.
- **Option 4 (Sharing one or more resources)**: This directly describes niche overlap, as it indicates that two species are utilizing the same resources.

6. **Conclusion**:
- The correct answer is **Option 4**, as it accurately reflects the concept of niche overlap by indicating that two species share one or more resources.