Which of the following option represent extinct species?

Options

A. Dodo (Mauritius) , Quagga (Africa)
B. Thylacine (Australia) , Stellar sea cow (Russia)
C. Three subspecies of Tiger (Bali , Javan and Caspian)
D. All of the above

Answer

To determine which options represent extinct species, we will analyze each option provided in the question.

### Step 1: Understand the concept of extinction
- **Definition**: Extinction occurs when there are no living individuals of a species left anywhere in the world.

### Step 2: Analyze each option
1. **Option 1: Dodo and Quagga**
- **Dodo**: The Dodo is an extinct bird that was native to Mauritius. It became extinct due to habitat loss and hunting by humans.
- **Quagga**: The Quagga was a subspecies of the plains zebra that became extinct in the late 19th century due to excessive hunting.
- **Conclusion**: Both Dodo and Quagga are extinct species.

2. **Option 2: Thylacine and Steller's sea cow**
- **Thylacine**: Also known as the Tasmanian tiger, it became extinct in the 20th century primarily due to hunting and habitat destruction.
- **Steller's sea cow**: This large marine mammal was hunted to extinction by the 18th century due to overhunting.
- **Conclusion**: Both Thylacine and Steller's sea cow are extinct species.

3. **Option 3: Three subspecies of Tiger (Wally, Java, and Caspian)**
- **Wally Tiger**: This is not a recognized subspecies; it may be a typographical error. However, the Java and Caspian tigers are indeed extinct.
- **Java Tiger**: Extinct due to habitat loss and hunting.
- **Caspian Tiger**: Also extinct, primarily due to habitat loss and hunting.
- **Conclusion**: The Java and Caspian tigers are extinct, but the mention of "Wally" is unclear.

4. **Option 4: All of the above**
- Since all the species mentioned in the previous options (Dodo, Quagga, Thylacine, Steller's sea cow, Java Tiger, and Caspian Tiger) are extinct, this option is also correct.

### Final Conclusion
- All the options provided represent extinct species. Therefore, the correct answer is **Option 4: All of the above**.

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