Onchosphere occurs in

Options

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

Answer

To solve the question "Onchosphere occurs in," we will follow these steps:

### Step 1: Understand the term "Onchosphere"
- The onchosphere is an embryonic form of certain parasitic worms, specifically associated with tapeworms. It is characterized by the presence of six hooks.

### Step 2: Analyze the options provided
- The options given are:
1. Ascaris
2. Fasciola
3. Tinea (Taenia)
4. Planaria

### Step 3: Evaluate each option
- **Ascaris**: This is a roundworm and does not have an onchosphere. Therefore, this option is incorrect.

- **Fasciola**: This refers to liver flukes, which also do not have an onchosphere. Hence, this option is incorrect as well.

- **Tinea (Taenia)**: This is a type of tapeworm. The onchosphere is indeed the embryonic form of Taenia, characterized by six hooks (hexacanth). This option is correct.

- **Planaria**: This is a flatworm but does not have an onchosphere. Thus, this option is incorrect.

### Step 4: Conclusion
- Based on the analysis, the correct answer is **Tinea (Taenia)**, as the onchosphere occurs in this type of tapeworm.

### Final Answer:
Onchosphere occurs in **Tinea (Taenia)**.

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