The correct answer is actin. Microfilaments are made form a ball-shaped protein called actin. These actins are globular proteins who are the ones responsible for the formation of microfilaments. It is mostly found in the eukaryotic cells.
Classification of living things takes into consideration of everything, except A. The number of cells the organism is found to have.
Some unicellular organisms are similar to animals because they have the ability to move.
Third option
