Final answer:
The correct option is a. Central Memory T cells are the type of memory T cells that circulate through secondary lymphoid tissues and have the ability to respond faster than naïve T cells upon encountering a pathogen.
Step-by-step explanation:
The correct answer to the question is a. Central Memory T cells. These are a subpopulation of memory T cells that reside in secondary lymphoid organs such as lymph nodes and the spleen. Central Memory T cells are known for their capacity to retain immunological memory and the ability to quickly mount an immune response upon reexposure to a pathogen they have previously encountered. This swift response is significantly faster than that of naïve T cells, which have not encountered a specific antigen before.
Effector T cells, on the other hand, are responsible for the immediate response during an ongoing immune reaction, but they do not possess the longevity of Central Memory T cells. Peripheral and Tolerant T cells refer to other subsets of T cells with different functions. Peripheral T cells circulate in the blood, while Tolerant T cells are typically unresponsive to specific antigens. Therefore, to maintain immunity against a disease, Central Memory T cells circulate through secondary lymphoid tissues, ready to respond quickly to re-infection.