in which animal ,pharyex can be everted ?

Options

A. Dugesia
B. Fasciola
C. Taenia
D. Ascaris

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the ability of an animal to evert its pharynx. Eversion refers to turning something inside out or outward.

2. **Identifying the Animal**: The animal in question is "Dugesia," which is a genus of flatworms belonging to the class Turbellaria. Dugesia is commonly known as planarians.

3. **Function of the Pharynx in Dugesia**: In Dugesia, the pharynx can be everted through the mouth opening. This means that the pharynx can be extended outward, functioning similarly to a proboscis.

4. **Mechanism of Eversion**: The pharynx lies within a cavity or pouch that is bounded by a muscular sheath. When the pharynx is everted, it protrudes out of the mouth, allowing the animal to feed by sucking in food.

5. **Conclusion**: Therefore, the animal in which the pharynx can be everted is Dugesia.

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