Which of the Following Statements About Secretion Is TRUE

Which of the following statements about secretion is TRUE?

A) The membrane of a secretory vesicle will fuse with the plasma membrane when it discharges its contents to the cell's exterior.
B) Vesicles for regulated exocytosis will not bud off the trans Golgi network until the appropriate signal has been received by the cell.
C) The signal sequences of proteins destined for constitutive exocytosis ensure their packaging into the correct vesicles.
D) Proteins destined for constitutive exocytosis aggregate as a result of the acidic pH of the trans Golgi network.