Branch of biology dealing with study of fishes is

Options

A. Fishery
B. Toxicology
C. Ichthylogy
D. Piscology

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the branch of biology that specifically focuses on the study of fishes.

2. **Identifying the Correct Term**: The correct term for the study of fishes is "ichthyology." This term is derived from the Greek words "ichthys," meaning fish, and "logos," meaning study.

3. **Differentiating Related Terms**:
- **Fisheries**: This term refers to the management and cultivation of fish populations, rather than the study of fish themselves.
- **Toxicology**: This branch of biology deals with the study of poisons and their effects, which is unrelated to fish.
- **Psychology**: This is the study of behavior and mind, and it does not pertain to fish or their study.

4. **Conclusion**: Based on the definitions and explanations provided, the branch of biology that deals with the study of fishes is "ichthyology."

**Final Answer**: Ichthyology

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