The interaction is detrimental to both the species, in

Options

A. Predation
B. Commensalism
C. Amensalism
D. Competition

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for an interaction between two species that is detrimental to both.

2. **Identifying Types of Interactions**: There are several ecological interactions to consider:
- **Predation**: Involves a predator and prey; one benefits (predator) while the other is harmed (prey).
- **Commensalism**: One species benefits while the other is neither helped nor harmed.
- **Amensalism**: One species is harmed while the other is unaffected.
- **Competition**: Both species compete for limited resources, leading to harm for both.

3. **Analyzing Each Interaction**:
- **Predation**: Not suitable since only the prey is harmed.
- **Commensalism**: Not suitable since one species benefits and the other is unaffected.
- **Amensalism**: Not suitable since only one species is harmed.
- **Competition**: This interaction fits the criteria as both species are harmed while competing for resources.

4. **Conclusion**: The interaction that is detrimental to both species is **competition**.

### Final Answer:
The interaction that is detrimental to both species is **competition**.

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