Final answer:
The maturation of dendritic cells indicates that they are becoming fully functional and capable of presenting antigens to naive T cells.
Step-by-step explanation:
Dendritic cells play a crucial role in the immune response by presenting antigens to naive T cells for activation. Therefore, the maturation of dendritic cells indicates that they are becoming fully functional and capable of presenting antigens to T cells. This process allows for the initiation of an adaptive immune response.