This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Physiology
Which pa of Henle loop is less permeable to water? 
Select and explain. 
A. Thin descending limb, B. Thin ascending segment/limb., C. Thick ascending segment/limb., D. Thick descending segment/limb.
B: Thin ascending segment/limb.
Answer: B: Thin ascending segment/limb. 
Explanation: Thin ascending segment/limb.REABSORPTION IN THIN ASCENDING LIMB:NaCl- reabsorption occurs -Due to high NaCl- permeability.Less permeable to water.Tubular fluid is iso-osmotic.