Which cells are classified as lymphoid cells?

Lymphoid cells are primarily associated with the immune system, and the most significant among them are lymphocytes, which are crucial for adaptive immunity. Lymphocytes are divided into several types, including B cells, T cells, and natural killer (NK) cells. These small white blood cells play key roles in recognizing and responding to pathogens.

The term "small white blood cells" is often used to refer to lymphocytes, distinguishing them from other types of blood cells. This classification specifically highlights the lymphoid lineage, which is associated with the production of antibodies and the direct killing of infected host cells.

The other options do not correctly classify lymphoid cells. Monocytes and erythrocytes belong to different categories of blood cells, with monocytes being part of the myeloid lineage involved in phagocytosis and erythrocytes being red blood cells responsible for oxygen transport. Granulocytes are another type of myeloid cell involved in the body's immune response, primarily through the release of enzymes and inflammatory mediators, and are not classified as lymphoid cells. Lastly, thrombocytes, or platelets, play a key role in blood clotting but do not fall under the lymphoid category either. Thus, the classification of lymphocytes