Measured in 2011 Dollars, the GDP Per Person of the World

Multiple Choice

Measured in 2011 dollars, the GDP per person of the world was $1,122 in 1820.  By 2010, the world's income per person had risen  to

A) nearly $1200, almost twice the level of 1820.
B) $2,422, almost four times the level of 1820.
C) a little more than $3,600, approximately six times the level of 1820.
D) $13,070, nearly twelve times the level of 1820.