As glomerular filtrate moves through the ascending loop of Henle, the filtrate becomes more dilute: why?

A. The ascending loop of Henle is permeable to water and ions

B. The ascending loop of Henle is permeable to ions but impermeable to water

C. The ascending loop of Henle is impermeable to water and ions

D. The ascending loop of Henle is permeable to water but not to ions