What factors are most responsible for the increasing length of life of

What factors are most responsible for the increasing length of life of Americans over the past 100 years?

a. Better nutrition and family planning options
b. Education concerning the need to reduce salt and fat in the diet
c. Improved medical care, including exciting new technologies
d. More efficient cancer screenings and early intervention

ESSAYBID ANSWER

ANS: A
Average increased life span over the past 100 years can be largely attributed to higher standards of living, better nutrition, a healthier environment, and having fewer children. Public health efforts such as immunization and medical care have also contributed.