The correct option is:
South Carolina encouraged immigration by offering grants of land to new immigrants; other areas of the country were unable to offer such land grants.
Immigration was important for the South Carolina new proprietors since they could only make a profit with new settlers. In 1670 the colony started granting land for rent for a penny an acre for five years.
The colony did receive migrants from other colonies and the British Isles, but in the first few years, most came from the British sugar islands in the Caribbean, particularly Barbados.