What process accounts for 10% of the body's obtained water and is derived from cellular activities?

The correct answer, derived from cellular activities, is oxidative metabolism. This process involves the conversion of nutrients, primarily carbohydrates and fats, into energy through a series of biochemical reactions. During these reactions, water is produced as a byproduct.

In aerobic conditions, oxidative metabolism occurs within the mitochondria, where glucose and fatty acids are oxidized, and molecular oxygen is used to ultimately produce ATP (adenosine triphosphate). The water generated during this process contributes approximately 10% of the total water that the body acquires.

Glycolysis, while related to energy production, does not directly contribute significant water as a byproduct in the broader sense of total body hydration. Fermentation typically occurs in anaerobic conditions and does not involve oxygen, and it produces byproducts such as lactic acid or ethanol instead of water. Transpiration refers to water loss through evaporation from plants and is not related to human cellular metabolism.