Branch of biology dealing with ageing is

Options

A. Gerontology
B. Psychobiology
C. Kalology
D. Dermatology.

Answer

**Step-by-Step Solution:**

1. **Understand the Question**: The question asks for the branch of biology that deals specifically with aging.

2. **Analyze the Options**: We have four options to consider:
- Gerontology
- Psychobiology
- Callology
- Dermatology

3. **Evaluate Each Option**:
- **Gerontology**: This is the study of aging, including the biological, psychological, and social aspects of aging. It encompasses all aspects related to aging, making it the most relevant option.
- **Psychobiology**: This field focuses on the relationship between biological processes and psychological phenomena. It does not specifically deal with aging.
- **Callology**: This branch studies beauty, particularly facial beauty. It is unrelated to aging.
- **Dermatology**: This is the study of the skin, including its structure, function, and disorders. While skin aging is a topic within dermatology, the field itself does not focus solely on aging.

4. **Conclusion**: Based on the evaluations, the correct answer is **Gerontology**, as it is the branch of biology that specifically deals with all aspects of aging.

**Final Answer**: Gerontology

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