The therapeutic angle here is oral rehydration therapy, the mainstay of managing secretory (e.g. cholera) diarrhea.
Mechanism of the disease vs the cure:
• Cholera toxin locks open the apical $$CFTR$$ chloride channel, so the gut pours out Cl, Na and water - CFTR drives the illness, it is not the treatment.
• The brush-border sodium-glucose cotransporter (SGLT1) stays fully active during the infection. It moves one glucose with two Na ions into the enterocyte, and water follows by osmosis.
Oral rehydration solution deliberately contains both glucose and sodium so that SGLT1 can couple their uptake and pull water back across the mucosa, correcting dehydration. This glucose-sodium coupling is precisely why ORS is effective.
The other choices fail: the Na/K-ATPase is a basolateral support pump (not the exploited luminal route), and aquaporin-2 is a renal ADH-dependent water channel unrelated to the gut.
\[\boxed{\text{SGLT (sodium-glucose cotransporter)}}\]