Scientists Have Always Known That Living Things Are Composed of Cells

Scientists have always known that living things are composed of cells. True or false?

A) True: Even ancient Greek scientists had access to microscopes and saw cells.
B) False: Scientists used to think a healthy body required just a balance of the humours: blood, phlegm, and yellow and black bile.
C) True: Because the smallest living things were one cell, it was obvious all living things were one or more cells.
D) False: There was no way to see cells prior to the invention of microscopes in the 1500s.
E) True: Living things had to be made of something bigger than just atoms.