Plz help pic is inserted

C

Explanation:

Organisms form carbon film when sediments cover the organisms and decay of organisms form hollows. When an organism is covered by sediment, it begins to decay. ... The hollow that forms on the sediment is the carbon film that contains what are called fossils of the organism

white blood cells or wbc s are mainly 2 types-

1.agranulocytes

2.granulocytes

the monocytes or macrophages of agranulocytes , dendritic cells which are accessory leucocytes, and b cells which is one type of lymphocytes   identify the antigens present on the pathogen's surface. these three cells are called antigen presenting cells(apc) which are phagocytes and destroy the antigens by secreting antitoxins. besides this leukocyte is always plays vital role in the immunity of the body.