The correct answer is D) The colonists in both grew tobacco.
What the colonies of Maryland and Virginia had in common was "the colonists in both grew tobacco."
The Southern colonies were Georgia, South Carolina, North Carolina, Virginia, and Maryland. It was John Rolfe in the Jamestown colony of Virginia that brought the first seeds of tobacco from the Caribean island of Trinidad. He used the seed in the fertile soil of Virginia and tobacco became the king in Virginia. The tobacco leaf was grayer and the taste was bitter that the European tobacco. Virginia and Maryland grew this crop that was exported to the old continent.