of the options you provided, re-absorption of water is not a direct function of the verebrate liver.
this is done by the excretory & urinary systems - mostly by large intestine to be more exact. The kidneys also play a role in water re-absorption, but they don't play as a significant of a role as the large intestines, which usues many many villi to re-absorb water beofre it's lost during excretion.
