Urinary bladder is absent in

Options

A. Bird
B. Snake
C. Crocodiles
D. All the above

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which of the given options lacks a urinary bladder. The options provided are birds, snakes, crocodiles, or all of the above.

2. **Analyzing the Options**:
- **Birds**: Birds have a unique excretory system where they do not have a urinary bladder. Instead, they excrete waste in a semi-solid form combined with feces to conserve water.
- **Snakes**: Similar to birds, snakes also lack a urinary bladder. They excrete waste in a semi-solid form, which helps them retain water.
- **Crocodiles**: Crocodiles, like birds and snakes, do not possess a urinary bladder and also excrete waste in a semi-solid form.

3. **Conclusion**: Since all three groups (birds, snakes, and crocodiles) do not have a urinary bladder and excrete waste in a way that conserves water, the correct answer is "all of the above."

### Final Answer:
Urinary bladder is absent in birds, snakes, and crocodiles (all of the above).

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