During the 1950s,people Lived on Average More Than Two Decades

Multiple Choice

During the 1950s,people lived on average more than two decades longer in developed countries than in developing ones.In the twenty-first century,the gap is ________.

A) less than 5 years
B) less than 10 years
C) less than 15 years
D) still the same
E) increased to 30 years