On a recent world tour, you saw a variety of species of animals. However, which of these species could you not have seen during your tour?

Options

A. Black Rhino
B. Snow Leopard
C. African Elephant
D. Passenger Pigeon

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks which animal species you could not have seen during your world tour. This implies that one of the options listed is extinct, meaning it no longer exists in the wild.

2. **Analyzing the Options**: The options provided are:
- Black Rhino
- Snow Leopard
- African Elephant
- Passenger Pigeon

3. **Identifying Extinct Species**: Among the options, we need to identify which species is extinct.
- The Black Rhino, Snow Leopard, and African Elephant are all species that still exist, although they may be endangered.
- The Passenger Pigeon, however, is known to be extinct.

4. **Reason for Extinction**: The Passenger Pigeon went extinct due to several factors:
- Over-exploitation: They were hunted extensively for their meat.
- Habitat loss: Their natural habitats were destroyed.
- Fragmentation: Their populations became too small to sustain themselves.

5. **Conclusion**: Since the Passenger Pigeon is extinct, it is the species that you could not have seen during your world tour.

**Final Answer**: The species you could not have seen during your tour is the Passenger Pigeon.

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