Final answer:
The correct statement about cortical collecting tubules is that they are lined by a simple epithelium containing two types of cells, which are principal and intercalated cells. These cells are integral for the regulation of ion and water balance as urine is processed within the kidney.
Step-by-step explanation:
The student asks which statement concerning cortical collecting tubules is always true. The correct answer is (A) They are lined by a simple epithelium containing two types of cells. In the kidney, the cortical collecting ducts are indeed lined with a simple epithelium comprised of two main cell types: principal cells, which are involved with sodium and water balance, and intercalated cells, which are involved with acid-base balance. These unique cellular compositions allow for the regulation of ion and water homeostasis as urine passes through the collecting ducts towards the ureter.
It is clear that the cortical collecting tubules are distinct from the loop of Henle, which is composed of both ascending and descending limbs with varying permeabilities and epithelial characteristics. The cortical collecting tubules do not have the same water permeability across all sections as it varies depending on hormonal influences like antidiuretic hormone. The cortical collecting ducts also do not continue from the Henle's loop directly but rather from the distal convoluted tubule, making some answer choices incorrect.