According to Madeline F. Green, what is one way that global citizenship different from national citizenship?
a. National citizenship promotes protectionist economic policies whereas global citizenship embraces free markets
b. National citizenship is an accident of birth whereas global citizenship is a choice and way of thinking
c. National citizenship is real whereas global citizenship is an illusion
d. National citizenship is free whereas global citizenship costs money
e. National citizenship is from Mars whereas global citizenship is from Venus