Where Did the Decline in Mortality Rates First Begin, and What

Where did the decline in mortality rates first begin, and what was responsible for it?

A) In East Asia, improvements to hygiene and diet lowered mortality rates.
B) In North America, mortality declined along with lower fertility rates and better diets.
C) In Africa, public health progress and reduction in birth rates helped mortality decline.
D) In Western Europe, mortality dropped when public health and hygiene improved.