Which of the following best describes how cells secrete products through the use of vesicles?
a. the cell allows substances contained in vesicles to diffuse across the membrane via passive transport.
b. the cell uses ATP to force substances contained in vesicles out of the cell through endocytosis.
c. vesicles fuse with the lipid bilayer and allow substances to leave the cell via exocytosis.
d. vesicles pump substances against a concentration gradient through active transport.
