An animal which became extinct a long time ago is:

Options

A. black buck
B. tiger
C. dinosaurs
D. python

Answer

To answer the question "An animal which became extinct a long time ago is:", we need to analyze the options provided: black bug, tiger, dinosaur, and python.

### Step-by-Step Solution:

1. **Analyze the Black Bug**:
- The black bug, also known as the Indian antelope, is a rare animal.
- Although it is rare and its population is low, it is still present in some areas.
- Therefore, it is not extinct.

2. **Analyze the Tiger**:
- The tiger is a large cat species with several subspecies.
- While some subspecies of tigers, such as the Javan, Caspian, and Bali tigers, have become extinct, the main species of tiger still exists today.
- Thus, the tiger itself is not extinct.

3. **Analyze the Dinosaur**:
- Dinosaurs are reptiles that existed millions of years ago.
- They first appeared around 231 million years ago and became extinct approximately 65 million years ago.
- Since dinosaurs have not existed for millions of years, they are classified as extinct.

4. **Analyze the Python**:
- Pythons are large snakes that are still present in various habitats around the world.
- Therefore, pythons are not extinct.

5. **Conclusion**:
- Based on the analysis, the only animal from the options that has been extinct for a long time is the **dinosaur**.

### Final Answer:
The animal which became extinct a long time ago is: **Dinosaur**.

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