Which of the Following Best Describes the History of Tariffs

Which of the following best describes the history of tariffs in the United States over the past 70 years?

A) Average tariff rates have not changed much since the early 1930s and are less than 5 percent.
B) Tariffs have declined overall since the early 1930s and now average just over 10 percent.
C) Tariffs were at their highest level in the 1970s and now average just over 10 percent.
D) Tariffs reached a maximum in the early 1930s and now average less than 5 percent