Which of the following is not a part of the nephron? 

The collecting duct is not a part of the nephron.

While Bowman's capsule, proximal convoluted tubule (PCT), and distal convoluted tubule (DCT) are all components of the nephron, the collecting duct is not considered a part of the nephron itself. Instead, the collecting duct receives filtrate from multiple nephrons and plays a crucial role in reabsorption and concentration of urine as it passes through the renal medulla.