Which is correctly matched

Options

A. Centipede, Prawn, Sea Urchin - Jointed appendages
B. Cockroach, Locust, Taenia - Metameric segamentation
C. Scorpion, Spider, Cockroach - Ventral solid nerve cord
D. Liver fluke, Sea Anemone, Sea Cucumber - Bilateral symmertry.

Answer

To determine which option is correctly matched, we will analyze each option one by one based on the characteristics of the organisms listed.

### Step-by-Step Solution:

1. **Option 1: Centipede, Prawn, Sea Urchin - Jointed Appendages**
- Centipedes and prawns belong to the phylum Arthropoda, which is characterized by jointed appendages.
- However, sea urchins belong to the phylum Echinodermata and do not have jointed appendages.
- **Conclusion:** This option is incorrect.

2. **Option 2: Cockroach, Locust, Taenia - Metameric Segmentation**
- Cockroaches and locusts are both arthropods and exhibit true metameric segmentation.
- Taenia, or tapeworms, belong to the phylum Platyhelminthes and do not exhibit true metameric segmentation; they show pseudo-segmentation.
- **Conclusion:** This option is incorrect.

3. **Option 3: Scorpion, Spider, Cockroach - Ventral Solid Nerve Cord**
- Scorpions, spiders, and cockroaches all belong to the phylum Arthropoda.
- Arthropods are known to have a ventral solid nerve cord.
- **Conclusion:** This option is correct.

4. **Option 4: Liver Fluke, Sea Anemone, Sea Cucumber - Bilateral Symmetry**
- Liver flukes belong to the phylum Platyhelminthes and exhibit bilateral symmetry.
- Sea anemones belong to the phylum Cnidaria and exhibit radial symmetry.
- Sea cucumbers belong to the phylum Echinodermata and exhibit biradial symmetry.
- **Conclusion:** This option is incorrect.

### Final Answer:
The correctly matched option is **Option 3: Scorpion, Spider, Cockroach - Ventral Solid Nerve Cord**.

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