An example for commensalism among the following is

Options

A. Liver fluke - Man
B. Abingdon tortoise - Goat
C. Orchid - Mango tree
D. Cuckoo - crow

Answer

**Step-by-Step Solution:**

1. **Understand the Concept of Commensalism**:
- Commensalism is a type of symbiotic relationship where one organism benefits while the other organism is neither helped nor harmed.

2. **Analyze the Given Options**:
- Option A: Liver fluke, man - This is a parasitic relationship where the liver fluke benefits at the expense of the man.
- Option B: Tortoise, goat - This does not represent commensalism; it is more of a neutral interaction.
- Option C: Orchid, mango tree - The orchid benefits by growing on the mango tree to access sunlight, while the mango tree is neither harmed nor benefited.
- Option D: Cuckoo, crow - This is also a parasitic relationship, as cuckoos often lay their eggs in the nests of crows, benefiting at the crow's expense.

3. **Identify the Correct Example**:
- Based on the analysis, the only option that illustrates commensalism is Option C, where the orchid benefits from the mango tree without affecting it.

4. **Conclusion**:
- Therefore, the correct answer is Option C: orchid and mango tree.