Which of the following statements about upward vertical mobility in the United States is NOT true?
a. Among men and women with the same level of education, vertical mobility is higher for men than for women.
b. In the U.S., a parent's level of education (whether they dropped out of high school, graduated from high school, or earned a college degree) has almost no impact on the amount of education their adult children earn.
c. There is less upward vertical mobility in the United States than in other Western democracies such as England, France, and Germany.
d. Formal education (such as, vocational training, college, etc) is a significant factor in upward vertical mobility within the United States.