Which one of the following processes is NOT regulated by the kidney?
This outcome reflects bioenergetics and thermodynamics, where internal energy, enthalpy and pressure-volume work describe evaporation and combustion. Option C captures this correctly because it satisfies first law and physiological energetics, consistent with textbook descriptions and experimental observations in physiology and thermodynamics.
Ref: Hill, Wyse and Anderson, Animal Physiology, 4th Edition, Chapter 7, Neurophysiology and Thermodynamics, discusses internal energy, enthalpy, work done, P(V2-V1), sweat evaporation and bioenergetics detailing physiological energy balance.