Which of the Following Is True of Foreign Trade Zones?​

Which of the following is true of foreign trade zones?​

A) ​These are areas that are physically outside U.S.soil but are considered to be inside U.S.commerce.
B) ​Goods entering foreign trade zones are subject to duty until they leave the zones.
C) Federal government has made it mandatory for U.S.companies to set up manufacturing plants within the foreign trade zones.
D) ​Companies that have set up manufacturing plants within the foreign trade zones are free from paying duty on defective materials.