As measured through post tax and post transfer income patterns, from World War II, then the U.S. has created: (w) no progress in reducing the gap in between the rich and poor. (x) substantial progress in reducing the gap in between rich and poor. (y) moderate progress in reducing the gap in between rich and poor. (z) negative progress in reducing the gap in between rich and poor.
Can anybody suggest me the proper explanation for given problem regarding Economics generally?