The correct answer is A) government records of the sale of the slaves.
The source that would give the most accurate number of slaves in the colonies was government records of the sale of the slaves.
When slave arrived in the American colonies in overcrowded spaces in the ships, the slaves were prepared to be sold directly to the owners of plantations or by slaves' auctions. At that moment, the government had a record of the sale of slaves. The first black slaves that arrived from Africa to America arrived at Jamestown Virginia, in 1619. Slaves were basically used in the southern colonies to work in the farm fields growing crops.