Which of these is given as an example of exocytosis in the body?

1. Exocytosis expels bulk material out of a cell by fusing a vesicle with the plasma membrane. 2. Examples include the secretion of extracellular matrix proteins and the secretion of neurotransmitters into the synaptic cleft by synaptic vesicles. 3. LDL uptake and bacterial engulfment both move material inward, so they are forms of endocytosis. 4. The sodium-potassium pump moves individual ions through a carrier protein rather than in a vesicle. _Source: OpenStax Biology (1st ed., CC BY 4.0), Ch 5 "Structure and Function of Plasma Membranes", section 5.4 Bulk Transport_