b. southern plantation owners needed more labor at lower costs
Explanation:
The slavery in the American companies developed because of the lack of labor force for the large plantations in the South that were making most of the profit for the colonies. Initially, the European settlers wanted to use the native people as a labor force, but because they spread diseases among them, the majority of the native population died out. This led to searching of an alternative for large and cheap labor force, and the Portuguese made the first step in it. After the other colonial powers understood about the possibility of getting slaves from Africa, they rushed to buy loads of them, including the British Empire. This resulted in a forceful movement of African people to the New World where they were used as slaves, a cheap and efficient labor force for the large plantations in the southern colonies.
