Kidneys process nitrogenous wastes by (1 point)separating water from nitrogenous wastes by passive diffusion. using cells to actively pump water across a membrane. storing the wastes as uric acid until they can be eliminated. pumping ions across membranes to separate water from waste products.

separating water from nitrogenous wastes by passive diffusion.

Passive diffusion happens usually in the primary filtering unit of the kidneys called nephrons. Water molecules along with salts, urea and glucose diffuse through the more minute parts of the kidney as part of the waste filtration process of the urinary system. 

explanation:

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