Ethnology is the science of

Options

A. Birds
B. Human races
C. Animals behaviour
D. Bird nests.

Answer

**Step-by-Step Solution:**

1. **Understanding Ethnology**: Ethnology is a branch of anthropology that focuses on the comparative study of cultures and human societies. It examines the characteristics, behaviors, and relationships among different human races.

2. **Analyzing the Options**:
- **Option A: Birds**: This option refers to the study of birds, which is known as ornithology. Therefore, this option is incorrect.
- **Option B: Human Races**: Ethnology specifically deals with the study of human races, their characteristics, and their social and cultural behaviors. This option is correct.
- **Option C: Animal Behavior**: The study of animal behavior is known as ethology, not ethnology. This option is also incorrect.
- **Option D: Birds Nest**: The study of birds' nests is called nidology. Thus, this option is incorrect as well.

3. **Conclusion**: After analyzing all the options, the only correct answer is that ethnology is the science of human races.

**Final Answer**: Ethnology is the science of human races (Option B).

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