D is the answer general anthony
By selling advanced tickets to settlers who planned to move west
In 1807, the British government passed an Act of Parliament abolishing the slave trade throughout the British Empire. Slavery itself would persist in the British colonies until its final abolition in 1838. However, abolitionists would continue campaigning against the international trade of slaves after this date.
The slave trade refers to the transatlantic trading patterns which were established as early as the mid-17th century. Trading ships would set sail from Europe with a cargo of manufactured goods to the west coast of Africa. There, these goods would be traded, over weeks and months, for captured people provided by African traders. European traders found it easier to do business with African intermediaries who raided settlements far away from the African coast and brought those young and healthy enough to the coast to be sold into slavery.
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