To compare an amoeba with a red blood cell, the most accurate statement is:
An amoeba is responsible for all functions, and a red blood cell is responsible for some functions.
This is correct because an amoeba is a single-celled organism that carries out all life functions (such as movement, feeding, and reproduction) on its own. In contrast, a red blood cell is a specialized cell that has a specific function (transporting oxygen) but does not perform all the functions necessary for life.