Question

the labor force in the american colonies shifted from indentured servitude to slavery because
indentured servants revolted more often, leading to slowdowns in production.
indentured servants refused to work on southern plantations for their contracted time.
enslaved africans were able to purchase their freedom over time, while indentured servants worked for life.
enslaved africans fulfilled labor demands for life, while indentured servants were free after their debt was paid.

Explanation:

Indentured servants had a limited - term contract to work off their debt and then gain freedom. Enslaved Africans, however, were forced into lifelong labor. As the demand for a permanent labor force grew in the American colonies, especially in plantation - based economies, the shift from indentured servitude to slavery occurred.

Answer:

enslaved Africans fulfilled labor demands for life, while indentured servants were free after their debt was paid