What two items were most important in the Indian Ocean trade during the post classical period

These included Kilwa, Sofala, Mombasa, Malindi, and others. The city-states traded with inland kingdoms like Great Zimbabwe to obtain gold, ivory, and iron. These materials were then sold to places like India, Southeast Asia, and China. These were Africa's exports in the Indian Ocean Trade.

Explanation: Hope this help :)

the answer is d. tariffs were raised by america's trading partners after the smoot-hawley tariff act, decreasing exports, and declining job rates.