Answer:
The correct answer is: macrophages.
Step-by-step explanation:
Macrophages are white blood cells, which means they participate in the immune response. What characterizes the Macrophages is that they are very big and have the ability to engulf and digest pathogens like bacteria and viruses, while they can also "eat" old cells or dysfunctional cells. This process is called phagocytosis.
Macrophages can be found all over the body, patrolling for pathogens in many different tissues, where they take alternative names that relate to the specialization they have in said tissue; for example, macrophages in the liver are called Kupffer cells, while macrophages in the nervous system are called microglia.
All macrophages share a common ancestor: the monocyte. The monocyte is a big white blood cell that travels through the bloodstream.
Monocytes and macrophages are part of the mononuclear phagocyte system, which also grants them the particularity of being APCs (antigen-presenting cells), a very important feature for the correct functioning of the immune system.