What Factor Plays a Key Role in Determining Why the Population

Multiple Choice

What factor plays a key role in determining why the population of Japan will most likely age more quickly than the U.S. population?

A) Japan's fertility rate has maintained its below-replacement rate for many decades.
B) Japan's medical advances surpass those of the United States.
C) The U.S. mortality rate is considerably higher than Japan's.
D) The lack of respect for the elderly in the United States hinders the quality of care they receive.