Final answer:
The earliest groups of forced labor used in America consisted of indentured servants, followed by slaves and later convicts.
Step-by-step explanation:
The earliest group of forced labor used in America consisted of Indentured servants. These individuals voluntarily entered into a contract, known as an indenture, in which they agreed to work for a set number of years, typically in exchange for passage to the American colonies.
However, as labor demands increased in the South and the supply of indentured servants became insufficient, the use of slaves became more prevalent. Slavery in America started with the arrival of the first African slaves in Jamestown, Virginia in 1619. Slaves were forcibly taken from Africa, sold at auctions, and became a permanent labor supply, with their children also being born into slavery.
Convicts were also used as forced labor in America. During the 18th and 19th centuries, many convicts were sentenced to hard labor, such as road construction or quarry work, as a form of punishment.
Therefore, the correct answer is a. Indentured servants, Slaves, Convicts.