Okay. So which of the following hormones is responsible for increasing the reabsorption of sodium in the distal tubule and the collecting duct? All right. Let's run through our answers here. So first, we have angiotensin I. Angiotensin I is not going to have any major effects. That's just going to need to get converted to angiotensin II. So that is definitely out. Now remember, angiotensin II is going to increase sodium reabsorption in our proximal tubule, but it's not going to directly affect any sodium reabsorption anywhere else in our renal tubule or collecting duct. So angiotensin II is out.
B is aldosterone, and that one is correct. Remember those "d" sounds, aldosterone, distal tubule, collecting duct. They all kind of go together. So our answer here is aldosterone.
Parathyroid hormone does operate in the distal tubule, but it is focusing on calcium, not sodium. So our answer here is going to be Aldosterone.
