T.solium passes on to secondary (intermediate) host at which stage?

Options

A. Onchosphere
B. Hexacanth
C. Cysticercus
D. Bladderworm

Answer

To determine at which stage T. solium (Pork Tapeworm) passes to its secondary (intermediate) host, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding T. solium**: T. solium is commonly known as the Pork Tapeworm and is classified as an endoparasite. It is digenetic, meaning it requires two hosts to complete its life cycle.

2. **Identifying Hosts**: The primary host for T. solium is humans, while the secondary or intermediate host is pigs.

3. **Life Cycle and Transmission**: The life cycle of T. solium involves the release of eggs through the feces of the primary host (humans). These eggs are in the form of a larva called an onchosphere.

4. **Infection of Intermediate Host**: Pigs become infected when they ingest the eggs (onchospheres) present in contaminated food or water.

5. **Conclusion**: Therefore, the stage at which T. solium passes to its secondary (intermediate) host is the onchosphere stage.

### Final Answer:
The correct option is **onchosphere**.

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