Question

which of the following processes involves the fusion of vesicles with the cell membrane?
exocytosis
endocytosis
simple diffusion
osmosis

Explanation:

Exocytosis is a process where vesicles fuse with the cell - membrane to release their contents outside the cell. Endocytosis is the opposite process where the cell membrane invaginates to form vesicles that take substances into the cell. Simple diffusion and osmosis are passive transport mechanisms that do not involve vesicle - membrane fusion.

Answer:

Exocytosis