Which statements are accurate descriptions of the african slave trade of the 1500s?
choose all answers that are correct.
a. african slavers refused to sell other africans into slavery outside of africa.
b. the portuguese and spanish were the first europeans to seek africans slaves to work in their colonies.
c. slavery first began in africa in the 1500s and then spread to other parts of the world in what became known as the middle passage.
d. during the 1500s, african slave traders began to sell slaves for the americas rather than for muslim lands to the north and east.