Identify the process by which the lost part of star fish can be regained in natural course.

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the process by which a starfish can regain a lost part naturally.

2. **Identifying the Process**: The process that allows the starfish to regrow lost parts is known as "regeneration."

3. **Explanation of Regeneration**: Regeneration is a biological process through which certain organisms can regrow lost or damaged body parts. In the case of starfish, if one of its arms is lost, it has the ability to regenerate that arm over time.

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