The correct answer is A. Mortality.
Mortality is the number of deaths in a population per unit of time. It is usually expressed as a rate per 1,000 or 100,000 people. Mortality can be caused by a variety of factors, including disease, injury, and old age.
Viability is the ability of an organism to survive and reproduce. It is a measure of the organism’s fitness. Viability can be affected by a variety of factors, including genetic factors, environmental factors, and the availability of resources.
Natality is the number of births in a population per unit of time. It is usually expressed as a rate per 1,000 or 100,000 people. Natality is affected by a variety of factors, including age structure, fertility rates, and immigration rates.
Vitality is a measure of the strength and energy of a person or thing. It is often used to describe the health of a population. Vitality can be affected by a variety of factors, including diet, exercise, and stress.