How Did the Profitability of the Slave Trade Compare to That

How did the profitability of the slave trade compare to that of other contemporary business ventures?

A) The slave trade was less profitable on the whole than other business ventures because of the high costs and risks involved.
B) The slave trade became increasingly dangerous and risky, so that by the 18th century its returns were minimal and most participants were bankrupted.
C) Profits from the slave trade in the 18th century were so lucrative that capital derived from the trade in human beings was used to capitalize the European Industrial Revolution.
D) The slave trade was little more profitable than most business activities of the age and was not a major source for the industrial revolution of Europe.