Correct option is C
Correct Answer:
Option 3
Explanation: In principal cells of the distal tubule and collecting duct, K⁺ secretion occurs mainly through
ROMK and
BK channels present on the apical membrane.
K⁺/Cl⁻ cotransporters (KCC1) help maintain intracellular ionic balance indirectly supporting K⁺ handling. The
Na⁺–K⁺–2Cl⁻ symporter (NKCC2) is located in the
thick ascending limb of the loop of Henle, not in principal cells of the distal tubule. Therefore, it is
not involved in K⁺ secretion by principal cells.
