Which of the following is most appropriately defined?

Options

A. Host is an organism which provides food to another organism
B. Amensalism is a relationship in which one species is benefited whereas the other is unaffected
C. Predator is an organism that catches and kills other organism for food
D. Parasite is an organism which always lives inside the body of other organism and may kill it

Answer

To solve the question of which of the following terms is most appropriately defined, we need to analyze the definitions provided for each term mentioned in the transcript.

### Step-by-Step Solution:

1. **Identify the Terms**: The terms mentioned are "host," "parasite," "MNC (Mutualism, Neutralism, Commensalism)," and "predator."

2. **Define Each Term**:
- **Host**: A host is an organism that provides food or shelter to another organism, typically a parasite. The definition should include both food and shelter.
- **Parasite**: A parasite is an organism that lives on or in a host and derives nutrients at the host's expense. It does not provide benefits to the host and often harms it.
- **MNC (Mutualism, Neutralism, Commensalism)**: This term refers to different types of species interactions. Mutualism benefits both species, commensalism benefits one species while the other is unaffected, and neutralism means both species are unaffected by each other.
- **Predator**: A predator is an organism that catches and kills other organisms for food. This definition is accurate as it describes the predatory behavior.

3. **Evaluate the Definitions**:
- The definition of **host** is partially correct but needs to specify that it provides food or shelter to a parasite.
- The definition of **parasite** is not explicitly given but is implied as it is described in relation to the host.
- The definition of **MNC** is incorrect as it misrepresents the relationships.
- The definition of **predator** is correct as it accurately describes the behavior of predators.

4. **Conclusion**: Among the terms analyzed, the definition of **predator** is the most appropriately defined. It accurately describes the role of predators in the ecosystem.

### Final Answer:
The term that is most appropriately defined is **predator**.

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