Final answer:
Option (b), The region of the nephron with simple cuboidal epithelium and prominent microvilli, which is primarily responsible for absorption, is the Proximal Convoluted Tubule (PCT).
Step-by-step explanation:
Which part of the nephron has simple cuboidal epithelium with microvilli for the majority of absorption?
The nephron region characterized by simple cuboidal epithelium with microvilli that plays a crucial role in absorption is the Proximal Convoluted Tubule (PCT). The cells lining the PCT possess a brush border of microvilli which increases their surface area for maximum absorption and secretion of solutes such as Na+, Cl-, and glucose. These cells are also rich in mitochondria to supply the ATP necessary for active transport processes.
In contrast, other nephron segments like the Distal Convoluted Tubule (DCT), Nephron Loop (specifically the ascending loop), and Renal Tubule CD have characteristics that do not match this description. The DCT, for example, has fewer microvilli compared to the PCT, indicating less absorption activity. Moreover, the ascending loop of the nephron does not have a brush border and is impermeable to water, focusing on ion transport instead of reabsorption of solutes and water.