Final answer:
The correct answer is b) Hydrology, hydraulics; hydrology studies the distribution of water in the environment, while hydraulics focuses on the behavior of fluids in motion, including how water flows through channels.
Step-by-step explanation:
For purposes of a riverine flood study, hydrology is the study of the distribution and circulation of water in the environment, and hydraulics is the study of fluids in motion and how water will flow through the channel. Therefore, the correct answer is b) Hydrology, hydraulics. Hydrology involves understanding how water behaves in the natural world, including precipitation patterns, vegetation, topography, land use, and soil characteristics, as well as its interactions with the hydrosphere, which includes rivers, lakes, and groundwater. Hydraulics, on the other hand, is specifically concerned with the engineering aspects of water in motion, analyzing how water flows through river channels and man-made structures.