Introduction:
Increase in longevity of life refers to the increase in the average lifespan of individuals in a population. This can be attributed to various factors such as advancements in healthcare, improved living conditions, better nutrition, and access to education. The increase in longevity of life is indeed an indicator of several positive outcomes.

1. Good quality of life:
The increase in longevity of life indicates a good quality of life. When individuals live longer, they have more opportunities to experience and enjoy life. They can spend more time with their loved ones, pursue their interests, and contribute to society. Increased longevity also means that individuals have a reduced risk of premature death, which is often associated with poor health and living conditions.

2. Improvement in health sector:
The increase in longevity of life is also an indicator of improvement in the health sector. Advancements in medical science, access to healthcare facilities, and better healthcare practices contribute to the increase in life expectancy. The development of vaccines, effective treatments for diseases, and improved healthcare infrastructure have played a significant role in improving health outcomes and prolonging life. Additionally, public health initiatives such as awareness campaigns, preventive measures, and early detection of diseases have contributed to the overall improvement in the health sector.

3. Better HDI:
The increase in longevity of life is closely linked to a better Human Development Index (HDI). HDI is a composite measure that takes into account factors such as life expectancy, education, and income levels. When the longevity of life increases, it positively impacts the life expectancy component of HDI. As a result, the overall HDI of a country or region improves. This indicates that individuals in that particular area have access to better healthcare, education, and overall well-being.

Conclusion:
In conclusion, the increase in longevity of life is indeed an indicator of several positive outcomes. It reflects a good quality of life, improvement in the health sector, and a better Human Development Index. These factors are interconnected and contribute to the overall well-being and progress of individuals and societies.

Option D]. all of the above