Which of the following drug is not needed to be present in tubular lumen for diuretic action?

Aldosterone receptor antagonist Osmotic diuretics Carbonic anhydrase inhibitor Thiazides spironolactone, eplerenone inhibit the aldosterone channels located on the basal side cells of collecting tubule, so they are not secreted in lumen. They filter across the glomerulus and in the nephron it will attract water, so it needs to come in the lumen They are also filtered in the tubule and inhibit carbonic anhydrase They are also fitered in lumen and they inhibit the Na+ Cl- channels in the DCT So the answer is '4'.