What is the not the consequence of Smoot-Hawley Tariff Act?

A．Trade protection were adopted in many countries to avoid negative impact from abroad, this is so called “beggar-thy-neighbor”.
B．This act prompted retaliation. Other countries implemented similar actions against the U.S.
C．International retaliatory moves led to a dramatic decline in the volume of world trade.
D．It helped the U.S. economy to recover from Great Depression and accelerates the growth of business in the U.S.