Final answer:
The root for the word microcyte is 'micro-,' referring to the small size of these red blood cells.
Step-by-step explanation:
The root for the word microcyte is C. micro-. Microcyte refers to a type of red blood cell that is smaller than the average size. The prefix 'micro-' is derived from Greek and means 'small,' while the suffix '-cyte' is derived from Greek and means 'cell.' Therefore, when these two are combined as 'microcyte,' it refers to a small cell.