Final answer:
Neutrophils, eosinophils, and basophils are types of white blood cells, each with specialized roles in the immune system including defense against infections, involvement in allergic reactions, and the release of histamines. The correct option is a. White blood cells
Step-by-step explanation:
Neutrophils, eosinophils, and basophils are types of white blood cells. These cells are critical components of the immune system. Neutrophils are the most abundant type of white blood cells in the bloodstream and are the body’s first line of defense against bacterial infections.
Eosinophils mainly target parasitic infections and are also implicated in allergic responses. Both eosinophils and basophils are capable of releasing histamines, which contribute to the inflammatory response. Basophils, while the least numerous of the white blood cells, play an essential role by secreting chemicals such as histamines, crucial for dilation and increasing the permeability of blood vessels during inflammation, and heparin, which inhibits blood clotting.
The morphology of these cells can be observed in blood smears, where neutrophils exhibit a multi-lobed nucleus and light lilac-stained granules, eosinophils have reddish-orange granules and a bi-lobed nucleus, and basophils have dark blue to purple granules with a bilobed nucleus. The correct option is a. White blood cells