Final answer:
The statement that T-cell survival depends on cytokines IL-7 and IL-15 is true. The false statement about T-cells is that MHC II is found on most body cells and MHC I exclusively on immune cells, as MHC II is on antigen-presenting cells and MHC I on almost all nucleated cells.
Step-by-step explanation:
The survival of T-cells is indeed reliant on the presence of certain cytokines. Specifically, IL-7 is crucial for the survival and homeostatic proliferation of naive and memory T-cells, and IL-15 is essential for the development and survival of natural killer cells and memory CD8+ T-cells. Thus, the statement that T-cell survival is dependent on the cytokines IL-7 and IL-15 is true.
In regard to the provided options, the false statement about T-cells is that 'MHC II is a receptor found on most body cells, while MHC I is found on immune cells only.' The correct information is that MHC II is found primarily on professional antigen-presenting cells, like dendritic cells, macrophages, and B cells, while MHC I is present on nearly all nucleated cells in the body, not just immune cells. Hence, option C from the list provided would be the false statement regarding T-cells.