**Core Concept:** Definition of health according to World Health Organization (WHO) encompasses various dimensions beyond mere absence of disease or disability. Health is a state of complete physical, mental, and social well-being.

**Why the Correct Answer is Right:** The definition of health provided by WHO is comprehensive and takes into account not only the absence of illness but also the overall well-being of an individual. It considers a person's physical, mental, and social aspects as integral components of health.

**Why Each Wrong Option is Incorrect:**

A. **Option A:** Absence of disease - While this is a part of health, it is incomplete as it fails to encompass the other dimensions mentioned by WHO.

B. **Option B:** Absence of disability - Similar to option A, this does not address the comprehensive nature of health according to WHO.

C. **Option C:** Physical well-being - While physical health is an essential aspect of health, it is not the entirety of WHO's definition.

D. **Option D:** Social well-being - Social aspects also play a crucial role in determining an individual's overall health, as per WHO's definition.

**Clinical Pearl / High-Yield Fact:** Understanding the WHO definition of health helps medical professionals provide holistic care that addresses the physical, mental, and social well-being of patients, leading to improved patient outcomes and satisfaction.

**Correct Answer:** **Option D:** Social well-being - According to the World Health Organization, health encompasses not only the absence of disease and disability but also includes the individual's physical, mental, and social well-being. This comprehensive definition highlights the importance of addressing various aspects of an individual's life to promote overall health.