The correct option is D Pinocytosis
The term pinocytosis means intake of liquid and is called as 'cell drinking'. Phagocytosis means intake of solid and is called 'cell eating'. These phenomena are readily observed in unicellular protists like protozoans.In pinocytosis and phagocytosis always there is formation of a vacuole-food vacuole or sap vacuole. In this respect the pinocytosis and phagocytosis are distinct from endosmosis and exosmosis, in which there is no vacuole formation.