Which of the Following Explains Changes in the Job of the Vice

Which of the following explains changes in the job of the vice president?

A) During the age of the nuclear missiles, many Americans believed that there should not be any learning curve for new presidents.
B) In 1848, Daniel Webster outlined additional roles that should become part of the vice presidency to make it a more significant office.
C) As the United States became a more global power, a need arose for the vice president to take on additional responsibilities
D) Based on the poor results of nine vice presidents assuming the presidency, initiatives have been taken so vice presidents spend more time with the president to be better prepared to take over the presidency if needed.