Radula and water vascular system are found in organism A and organism B respectively. Identify A and B.

Options

A. A - Locusta, B - Chiton
B. A - Sea hare , B - Betta
C. A - Tusk shell , B - Sea urchin
D. A - Apis , B - Bombyx

Answer

To solve the question regarding the identification of organisms A and B based on their respective anatomical features, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Features**:
- Organism A has a radula.
- Organism B has a water vascular system.

2. **Identifying Organism A (Radula)**:
- The radula is a specialized feeding structure found in certain mollusks. It is a tongue-like organ with tiny teeth used for scraping food.
- Common examples of organisms that possess a radula include snails, slugs, and certain types of mollusks like chitons.

3. **Identifying Organism B (Water Vascular System)**:
- The water vascular system is a unique feature of echinoderms, which includes organisms such as sea stars, sea urchins, and sea cucumbers.
- This system is used for locomotion, feeding, and respiration.

4. **Analyzing the Options**:
- **Option 1**: Locust and Chiton - Incorrect (Locust is an insect, Chiton has a radula).
- **Option 2**: Seahorse and Beta - Incorrect (Seahorse is a fish, Beta is a fish too, neither has a radula).
- **Option 3**: Tusk Shell (has a radula) and Sea Urchin (has a water vascular system) - Correct.
- **Option 4**: Apis and Bombix - Incorrect (Both are insects).

5. **Conclusion**:
- Organism A is **Tusk Shell** (which has a radula).
- Organism B is **Sea Urchin** (which has a water vascular system).

### Final Answer:
- Organism A: Tusk Shell
- Organism B: Sea Urchin