Final answer:
B cells develop into plasma cells, which produce antibodies. Macrophages can both phagocytize pathogens and produce inflammation-promoting chemicals. Macrophages are also the phagocytic cells in the immune system.
Step-by-step explanation:
The cell type that can develop into plasma cells is D) B cells. B cells are part of the adaptive immune system. Upon activation by antigens, they differentiate into plasma cells, which are specialized in producing antibodies. These antibodies are crucial in identifying and neutralizing pathogens such as viruses and bacteria.
The immune system cell capable of both phagocytizing pathogens and producing chemicals that promote inflammation is A) Macrophages. Macrophages are a type of white blood cell that engulfs and digests cellular debris and pathogens, and they also release pro-inflammatory signals to recruit other immune cells.
Regarding the phagocytic cells, the correct answer is b) macrophage. Macrophages play a key role in both innate and adaptive immunity by engulfing pathogens and presenting antigens to T cells, leading to an immune response.