Amensalism is an association between two species where

Options

A. one species is harmed and other is benefitted
B. one species is harmed and other is unaffected
C. one species is benefitted and other is unaffected
D. both the species are harmed.

Explanation

### Step-by-Step Solution:

1. **Understanding Amensalism**:
- Amensalism is a type of interaction between two species in an ecosystem. It is important to define what it entails.

2. **Defining the Interaction**:
- In amensalism, one species is harmed while the other species remains unaffected. This means that one species suffers negative effects from the interaction, while the other does not gain or lose anything.

3. **Examples of Amensalism**:
- A classic example of amensalism is the interaction between cattle and grass. When cattle walk through a grassy area, they may trample on the grass. Even though the cattle do not eat that particular grass, their movement can cause damage to it.

4. **Clarifying Misconceptions**:
- It is essential to differentiate amensalism from other types of interactions, such as predation or competition. In predation, one species benefits at the expense of another, while in amensalism, the unaffected species does not benefit from the interaction.

5. **Conclusion**:
- Therefore, the correct description of amensalism is that one of the species involved in the interaction is harmed, whereas the other is unaffected.

### Final Answer:
Amensalism is an association between two species where one species is harmed, and the other is unaffected.

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