the hypothesis states “increased pressure should cause the kidneys to increase output of fluid.”
you have to recall that the driving force of the glomerular filtration rate is determined by hydrostatic and oncotic pressure differentials between the glomerulus and Bowman’s space. thus, this increased rate will further filter solutes into the nephron, increasing urine output.
Why can't it be increased blood flow to the bladder? Wouldn't that cause increased pressure? Or is that option incorrect because it's unrelated to the system that's involved in the regulation of urine output?