Duct of Bellini is formed by the combining of
Collecting ducts
Distal convoluted tubule
Ureter
Papillae
Proximal Convoluted Tubule (PCT), Loop of Henle, Distal Convoluted Tubule (DCT) and Collecting Duct -
Collecting Duct:
The collecting ducts combine to form still larger ducts called the duct of Bellini. Hence the correct option is Collecting ducts