How many animals in the given list have gills for respiration ?
Earthworm , Frog, Fish, Insects, Reptiles, Aquatic arthropods, Flatworm, Molluscs, Birds

Options

A. Six
B. Four
C. Three
D. Five

Answer

To determine how many animals in the given list have gills for respiration, we will analyze each animal one by one:

1. **Earthworm**: Earthworms respire through their skin via diffusion. They do not have gills.

2. **Frog**: Frogs do not have gills; they respire through their moist skin and lungs as adults.

3. **Fish**: Fish have gills, which they use for respiration in water.

4. **Insects**: Insects do not have gills; they have a tracheal system for respiration.

5. **Reptiles**: Reptiles have lungs for respiration; they do not possess gills.

6. **Aquatic Arthropods**: Aquatic arthropods, such as crabs and shrimp, have gills for respiration.

7. **Flatworm**: Flatworms respire through diffusion across their body surface; they do not have gills.

8. **Molluscs**: Many molluscs, such as clams and squids, have gills for respiration.

9. **Birds**: Birds have lungs for respiration and do not have gills.

Now, let's summarize the findings:

- **Fish**: Have gills (1)
- **Aquatic Arthropods**: Have gills (2)
- **Molluscs**: Have gills (3)

Thus, the total number of animals from the list that have gills for respiration is **3**.

### Final Answer: 3 animals have gills for respiration.

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