Final answer:
Out of the options provided, the kidneys (C) are the organs located in the retroperitoneal space, where they play a crucial role in filtering blood.
Step-by-step explanation:
The retroperitoneal space contains certain organs that are located behind the parietal peritoneum in the abdominal cavity. Out of the options provided, the organ found in the retroperitoneal space is C. Kidneys. The kidneys are vital organs that are well protected by muscle, fat, and ribs, and are responsible for filtering blood, among other functions. They receive a significant amount of cardiac output, approximately 25%, indicating their importance in the circulatory system. It’s worth noting that while the pancreas is also retroperitoneal, it was not listed among the answer choices provided.