The correct option is D W. H. Lewis
Pinocytosis is a mode of endocytosis in which small particles are brought into the cell, forming an invagination, and then suspended within small vesicles. These pinocytotic vesicles subsequently fuse with lysosomes to hydrolyze (break down) the particles. This process requires a lot of energy in the form of adenosine triphosphate (ATP), the chemical compound mostly used as energy in the majority of animal cells. Using time-lapse photography to study tissue culture cells, W. H. Lewis in 1931 described what seemed to be a curious phenomenon in which small amounts of culture medium were trapped in invaginations of the plasma membrane and then pinched off to form small cytoplasmic vesicles. As the entire process appeared much like some form of organized cell drinking, Lewis termed the phenomenon pinocytosis.