Urinary bladder is present in

Options

A. peacock
B. crocodile
C. snake
D. mouse

Answer

To determine where the urinary bladder is present, we can analyze the characteristics of different classes of animals.

### Step-by-Step Solution:

1. **Identify the Classes of Animals**: We need to consider the classes of animals mentioned in the question: mammals, birds, and reptiles.

2. **Examine Mammals**:
- Mammals are known to have a urinary bladder. This organ is used to store urine before it is excreted.
- Example: A mouse is a mammal and has a urinary bladder.

3. **Examine Birds**:
- Birds, such as peacocks, do not have a urinary bladder.
- This absence is an adaptation to reduce body weight for flight.

4. **Examine Reptiles**:
- Reptiles, such as crocodiles and snakes, also lack a urinary bladder.
- They excrete waste in a different manner, often directly into their environment.

5. **Conclusion**:
- Based on the analysis, the urinary bladder is present in mammals but absent in birds and reptiles.
- Therefore, the correct answer to the question is that the urinary bladder is present in the mouse.

### Final Answer:
The urinary bladder is present in the mouse.

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