The embryo known as onchophere occurs in

Options

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

Answer

To answer the question regarding the embryo known as onchosphere, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Term**: The term "onchosphere" refers to a specific type of larval stage in certain parasitic organisms.

2. **Determine the Organism**: Onchosphere is specifically associated with tapeworms, which belong to the genus Taenia.

3. **Understand the Context**: Tapeworms are endoparasites, meaning they live inside the host's body and absorb nutrients from it. The onchosphere is a larval form that is part of the lifecycle of these tapeworms.

4. **Identify the Specific Species**: The two common species of Taenia that are often mentioned are Taenia solium (pork tapeworm) and Taenia saginata (beef tapeworm). Both species produce onchospheres during their lifecycle.

5. **Conclude the Answer**: Therefore, the embryo known as onchosphere occurs in tapeworms, specifically in the genus Taenia.

### Final Answer:
The embryo known as onchosphere occurs in tapeworms, specifically in the genus Taenia.

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