Final answer:
The desert commonly known as "The Empty Quarters" in Saudi Arabia is called the Rub' al Khali (option B).
Step-by-step explanation:
The desert commonly known as "The Empty Quarters" in Saudi Arabia is called the Rub' al Khali (option B). It is the largest contiguous sand desert in the world and covers about 25 percent of Saudi Arabia. The Rub' al Khali is extremely dry and mostly uninhabited, although oil discoveries have brought temporary settlements to the region.