Which Statement Is True of the Modern World's Population

Which statement is true of the modern world's population?

A) seems to be stabilizing at about 6 ½ billion people
B) is increasing exponentially and may have dire results
C) may decline by mid-century if AIDS and other communicable diseases are not controlled
D) is concentrated mostly in Africa
E) is predicted to be rebalanced sometime during the 21st  century by a global catastrophe