The correct answer is active transport by endocytosis.
Cells use active transport by endocytosis which allows it to take in other cells or large molecules.
Active transport is termed as movement of molecules across membrane. The movement comes from low concentrated region to a high concentrated region.
Endocytosis is a form of bulk transport whereby, cells transports molecules. For example proteins into the cell by the way of engulfing them in a process which uses energy.
Endocytosis is used by cells reason being that the chemical substance which is crucial to them are molecules, and they are large non polar and they cannot pass through cell membrane by means of active.