Which one of the following show brood parasitism?

Options

A. Crow
B. Koel
C. Squirrel
D. Pigeon

Explanation

To determine which of the following shows brood parasitism, we need to understand what brood parasitism is and then analyze the options provided.

### Step-by-Step Solution:

1. **Define Brood Parasitism**:
- Brood parasitism is a reproductive strategy where one species (the parasite) lays its eggs in the nest of another species (the host). The host then raises the young of the parasite, often at the expense of its own offspring.

2. **Analyze the Options**:
- **Option A: Crow**: Crows are not known for brood parasitism. They typically raise their own young.
- **Option B: Coel**: The Coel (also known as the Common Cuckoo) is a well-known example of a brood parasite. It lays its eggs in the nests of other birds, such as crows, tricking them into raising its young.
- **Option C: Squirrel**: Squirrels do not exhibit brood parasitism. They care for their own young.
- **Option D: Pigeon**: Pigeons also do not engage in brood parasitism; they raise their own chicks.

3. **Conclusion**:
- Based on the definitions and analysis of the options, the correct answer is **Coel**. The Coel is the only one among the options that shows brood parasitism by laying its eggs in the nests of other birds.

### Final Answer:
The correct option that shows brood parasitism is **Coel**.

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