Branch of biology dealing with ageing is

Options

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

Answer

**Step-by-Step Solution:**

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

2. **Analyzing the Options**: The options given are:
- A) Gerontology
- B) Psychobiology
- C) Callology
- D) Dermatology

3. **Defining Each Term**:
- **Gerontology**: This is the study of aging, encompassing the social, cultural, psychological, cognitive, and biological aspects of aging.
- **Psychobiology**: This field studies the biological basis of psychological processes and behavior, not specifically focused on aging.
- **Callology**: This term is not widely recognized in the context of biology or aging.
- **Dermatology**: This is the branch of medicine that deals with the skin and its diseases, not specifically related to aging.

4. **Identifying the Correct Answer**: Based on the definitions, gerontology is the only field that directly addresses the study of aging. The term "geron" means old, and "logy" means study, which confirms that gerontology is indeed the study of aging.

5. **Conclusion**: Therefore, the branch of biology dealing with aging is **Gerontology**.

**Final Answer**: The correct option is A) Gerontology.

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