Which set of processes comprises the hydrological cycle in watershed management?

• A. Precipitation, evaporation, condensation, and infiltration.
• B. Decomposition, nutrient cycling, photosynthesis, and respiration.
• C. Evaporation, condensation, precipitation, and deposition.
• D. Precipitation, evaporation, condensation, infiltration, runoff, and transpiration.

Answer: (D)

In watershed hydrology, the cycle focuses on how water moves through the atmosphere, land, and vegetation within a watershed. Water arrives as precipitation, then some infiltrates the soil to become groundwater while some runs off over the surface toward streams. Plants contribute to the cycle through transpiration, releasing water vapor from leaves. Evaporation lifts water from soil and water bodies back into the air, and condensation in the atmosphere forms the clouds that lead to more precipitation. This full sequence—precipitation, infiltration, runoff, evaporation, transpiration, and condensation—tollows water as it cycles within the watershed and back into the atmosphere. The other options miss essential pieces: one omits runoff and transpiration, another emphasizes biological processes, and another includes deposition or omits key hydrologic pathways.