In medieval times, the average lifespan of human beings was way lesser than what it is now. The advancements in modern medicine and other technological advancements have made it possible. _________________________.
a. Polio has been almost eradicated by improvements in science.
b. In medieval times, the science of medicine was not yet developed.
c. As with more and more advancements in science, the average lifespan of humans keeps increasing.
d. Science is very important for a long and healthy life.