Branch of biology dealing with study of organisms in outer space is :

Options

A. Exobiology
B. Ethology
C. Euphenics
D. Ethnology

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the branch of biology that focuses on the study of organisms in outer space.

2. **Identifying Relevant Terms**: In biology, there are various branches that study different aspects of life. The key term here is "organisms in outer space."

3. **Recalling Biological Branches**:
- Ethology: This is the study of animal behavior.
- Euphenics: This relates to the study of good appearance or face reading.
- Ethnology: This is the study of cultures and social behaviors.

4. **Focusing on Outer Space**: Among the branches mentioned, none of them relate to outer space. However, there is a branch known as Exobiology.

5. **Defining Exobiology**: Exobiology, also known as astrobiology, is the study of life in the universe, including the possibility of life on other planets and the conditions that could support such life. It encompasses the study of organisms that might exist in outer space.

6. **Conclusion**: Based on the definitions and focus areas of the branches of biology, the correct answer to the question is Exobiology.

**Final Answer**: Exobiology

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