What was the main resource Europeans exporting from African, especially the Portuguese, starting in the 1500s?

ok well i know that there are a few different ones,  gold, precious stones, wood, ivory, silver, ebony.

Explanation:

hope this helps have a good day

answer; ///i do believe that the correct answer for the above is ( which states would be free and which states would have check first good

what are the choices btw if it was me id say the lack of money to continue with education