In animals belonging to phylum Platyhelminthes, locomotory organelles are______.

Explanation

**Step-by-Step Solution:**

1. **Identify the Phylum:** The question asks about animals belonging to the phylum Platyhelminthes, which are commonly known as flatworms.

2. **Understand Locomotory Organelles:** Locomotory organelles are structures that enable movement in organisms. In the case of Platyhelminthes, we need to identify what these structures are.

3. **Recognize the Role of Cilia:** In Platyhelminthes, cilia are the primary locomotory organelles. Cilia are tiny hair-like structures that cover the surface of these organisms.

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