Using Radiolabeled Amino Acids, Palade and Colleagues Defined the Pathway $\rightarrow$

Using radiolabeled amino acids, Palade and colleagues defined the pathway taken by secreted proteins. Which sequence represents that pathway?

A) Rough ER $\rightarrow$ smooth ER $\rightarrow$ Golgi $\rightarrow$ secretory vesicles $\rightarrow$ cell exterior
B) Rough ER $\rightarrow$ smooth ER $\rightarrow$ Golgi $\rightarrow$ endosomes $\rightarrow$ cell exterior
C) Rough ER $\rightarrow$ Golgi $\rightarrow$ lysosomes $\rightarrow$ cell exterior
D) Rough ER $\rightarrow$ Golgi $\rightarrow$ secretory vesicles $\rightarrow$ cell exterior