Which type of cells produce chemicals that recruit other cells such as phagocytes during an immune response?

The correct choice is T-Lymphocytes, specifically a subset known as helper T cells. These cells play a crucial role in the immune response by producing signaling molecules called cytokines. Cytokines help to recruit and activate other immune cells, including phagocytes like macrophages and neutrophils, which are essential for engulfing and destroying pathogens. This recruitment is a vital part of the immune response, ensuring that the body can effectively respond to and clear infections.

In contrast, plasma cells are effector B-cells responsible for producing antibodies, which help target pathogens but do not directly recruit other immune cells. Lymph vessels are part of the lymphatic system and play a role in transporting immune cells and fluid throughout the body but do not produce chemicals to recruit other cells. B-Lymphocytes, while important for antibody production and part of the adaptive immune response, do not have the same direct role in recruiting other immune cells as T-Lymphocytes do.