Final answer:
On a typical day, an average adult excretes approximately 10 liters of water in the gastrointestinal (GI) tract. This is the result of continuous excretion of water in the form of digestive juices, the reabsorption of water from the food and drinks, and the regulation of water levels by the kidneys.
Step-by-step explanation:
The correct answer is c) 10 liters.
On a typical day, an average adult takes in about 2500 mL of aqueous fluids. This includes water consumed through beverages and water content in solid foods. However, the body does not excrete all of this water through the digestive tract. Only about 100 mL of water is excreted in the GI tract daily, while the remaining water is reabsorbed along with the water from food and drinks.
In addition to the water intake, the body also loses water through other routes such as urine, evaporation from the skin, and air expelled from the lungs. The kidneys play a vital role in regulating water levels in the body, conserving water when dehydrated and expelling excess water when necessary. Overall, the total internal secretion of water into the GI tract is approximately 7 to 10 liters per day.